THE  LIBRARY 

OF 

THE  UNIVERSITY 
OF  CALIFORNIA 


PRESENTED  BY 

PROF.  CHARLES  A.  KOFOID  AND 
MRS.  PRUDENCE  W.  KOFOID 


ROMANCE 

OF   THE 

INSECT    WORLD 


NEST    OK    A    TREE    ANT. 


ROMANCE 


OF   THE 


INSECT   WORLD 


BY 


L.    N.    BADENOCH 


WITH  ILLUSTRATIONS 
BY  MARGARET  J.   D.  BADENOCH  AND   OTHERS 


LARVA    OF    THE   CADDIS-FLY  (T richoptera). 


Eonfoon 
MACMILLAN     AND    CO. 

AND    NEW    YORK 
1893 

The  Right  of  Translation  and  Reproduction  is  Reserved 


Copyright  1893 
BY  MACMILLAN  AND  Co. 


RICHARD  CLAY  AND  SONS,  LIMITED, 
LONDON  AND  BUNGAY 


V. » b 


TO 

MY    MOTHER 

A 

TOKEN    OF    AFFECTION 


^345849 


CONTENTS 

CHAPTER  I. 

METAMORPHOSES    OF    INSECTS. 

Character  of  life-history  of  insects — Metamorphoses  of  the  butter- 
fly, beetles,  &c.  — "Similarly  changing"  insects— The  two 
series  Heteromorpha  and  Homomorpha — True  metamorphic 
stages  considered  in  detail— Egg— Larva— Shelters  for  ap- 
proaching change — Meaning  of  pupa  and  other  terms  applied 
to  stage — Nature  of  condition  in  insects  which  undergo  com- 
plete metamorphoses — Signs  of  returning  life — Assumption 
of  imago  state — Pseudo-imago — Subsequent  career — Old  idea 
of  metamorphoses — Modern  theory — Study  of  structures  im- 
plicated—  External  —  Modifications  of  internal  organs — Ex- 
planation of  metamorphoses — Apparent  suddenness  of  changes 
—Of  the  death-like  period  of  quiescence 


CHAPTER    II. 

FOOD    OF    INSECTS. 

Chief  sources  of  food — Almost  limitless  choice  from  vegetable 
world— Death's  Head  Moth  as  a  thief— Animal  feeders- 
Parasitic  Hymenoptera  and  others — Mighty  business  of  insect- 
parasites  upon  insects— Larva  of  the  Tabby — Another  strange 
food  of  animal  derivation — Ants  and  their  aphides — Intimate 
connection  of  ants  with  other  insects — Usual  restriction  of 


CONTENTS 

PAGE 

insects  to  vegetable  or  animal  diet— Change  of  diet  at  different 
stages  of  life — Need  of  nurses  by  the  young  of  the  Social 
Hymenoptera — Livelihood  without  industry — Slave  makers — 
Honey  Ant— Analogy  between  its  economy  and  that  of  bee  in 
storage  of  food — Harvesting  ants  in  the  East,  in  Europe,  in 
America — Time  of  feeding— Instruments  of  nutrition— High 
adaptation  of  Lepidoptera  to  floral  diet— Means  of  procuring 
food — Stratagem  of  ant-lion 34 


CHAPTER    III. 

HERMIT     HOMES. 

Methods  of  formation  of  homes  constitute  remarkable  phase  of 
habits  and  economy  of  insects— A  home  necessary  by  reason 
of  nature  of  life  of  insects— Habitations  of  solitary  insects  for 
their  young — Solitary  bees — Solitary  wasps — Galls— Habita- 
tions of  solitary  larvoe  for  own  use — Homes  of  solitary 
architects  being  perfect  insects  for  own  use,  and  also  for 
that  of  their  young — Trap-door  and  other  spiders 71 


CHAPTER    IV. 

SOCIAL   HOMES. 

Diversity  of  method  of  insect  architecture,  its  beauty  and  size— 
The  word  architecture  as  applied  to  this  portion  of  insect 
economy — Societies  of  social  caterpillars — Three  types  of  nests 
of  ants — Home  of  common  Wood  Ant — external  conformation 
— internal  plan— doors— formation  and  regulation  of  society 
— A  solitary  "  queen"  as  founder  of  a  colony — Singularity  of 
Wood  Ant  in  preference  for  open-air  life— Mason  Ants— Extra- 
ordinary dimensions  of  homes  of  Saiiba  or  Coushie  Ants — 
Their  leaf-cutting  propensities — Mushroom-growers — Mason 
Ants  of  New  World ;  their  disks,  roads,  refuse  heaps, 
store-rooms,  nurseries,  lumber-closets,  position  as  farmers,  &c. 
— F.fuliginosa  and  other  carpenters — Standing  army  of  Bull's 
Horn  Acacia — Ants  as  guardians  of  other  plants — Remark- 
able pensile  nests  of  Crematogaster,  Myrmica  Kirbii, 
CEcophylla  sinaragdina,  &c 118 


CONTENTS  xi 

CHAPTER    V. 

SOCIAL  HOMES  (continued). 

I'AGE 

So-called  humble-bees — Eighteen  or  twenty  species  in  this  country 
— Comparison  of  their  habitations  with  the  hive — Description 
of  nest  of  Carder — The  coping  of  moss — Interior — Dispersion 
of  company  and  hybernation  of  females — Work  of  latter  in 
Spring — Deep  burrowers  among  British  Wild  Bees — Honey- 
bees in  East — Stingless  Meliponae  and  Trigonae  of  South 
America  and  their  homes — Supposed  presence  of  several 
fertile  females — Sentinels  to  guard  the  gates — True  social 
wasps — Their  building-material  and  disposition  of  combs- 
Particulars  of  home  of  common  English  wasp — British  tree- 
wasps — The  papery  envelope — Nest  of  hornet — Description  of 
combs  of  Polistes  and  Icarias,  without  cover — Apoica  has  a 
cover  but  not  distinct— Card-board  makers — Wasps  as 
honey-gatherers 154 

CHAPTER    VI. 

DEFENCES    OF    INSECTS,    OR   PROTECTION  AS    DERIVED    FROM 
COLOUR. 

Need  of  insects  of  means  of  defence — Adaptation  of  their  external 
colouring  to  conditions  of  life — Protective  Resemblances — 
Herein  find  explanation  of  first  and  most  wide-spread  use  of 
colour  among  animals— Principle  of  adaptive  colouring  solved 
by  theory  of  natural  selection  —  Commonness  of  general 
harmony  between  colouring  of  insects  and  tints  of  nature — 
Imitative  tints  of  undersides  of  wings  of  butter-flies — Special 
Protective  Resemblance — "Stick  caterpillars"  and  others- 
Leaf  butterflies — British  and  European  Moths — Among  Or- 
thoptera — Tropical  "walking-leaf"  and  "walking-stick" 
insects — Other  insects  and  spiders — Alluring  Colouring — Re- 
semblance of  Mantises  and  Spiders  to  flowers — To  excreta  of 
birds — Changes  of  colour  corresponding  to  changes  of  environ- 
ment— Di-  and  Polymorphism — Their  value — Meaning  obscure 
— Variable  Protective  Resemblance  in  pupae — In  larvae — In 
colours  of  cocoons — In  perfect  insects — Variable  Protective 
Resemblance  and  the  origin  of  colour — Power  of  adjustment 
of  colour  is  adaptive,  and  is  produced  and  maintained  by 
natural  selection 203 


CONTENTS 


CHAPTER  VII. 

DEFENCES    OF    INSECTS,  OR   PROTECTION    AS    DERIVED    FROM 

COLOUR  (continued}. 

FACE 

A  conspicuously  coloured  group — Objection  to  colour — Different 
modes  of  msects  of  maintaining  existence  ;  possession  of  nause- 
ous properties,  irritating  hairs  and  spines,  the  sting,  hardness  of 
substance,  wonderful  vitality,  capacity  for  increase,  attitudes — 
Association  of  bright  colour  with  distasteful  qualities — Bright 
colour  as  a  warning  ;  its  value — Various  combinations  of 
means  of  defence — Resemblance  between  Warning  Colours 
and  patterns ;  determining  causes  of  the  repetition — Distinction 
between  Warning  Colours  and  those  produced  by  courtship — 
Sexual  colouring  made  use  of  for  warning  ;  its  similarity — Con- 
spicuous and  nauseous,  but  non-vital  parts — One  meaning  of 
broad  expanse  of  wing  of  showy  butterflies — Mimicry — Bates 
first  to  explain  the  facts — Butterflies  that  are  objects  of 
mimicry  in  tropics — Their  unpalatability  indicated  by  conspicu- 
ousness  and  abundance — True  Mimicry  as  distinct,  from  all 
warning  appearances — The  term  Mimicry — Mimicry  a  phase 
of  Protective  Resemblance — Mimicry  of  American  butterflies, 
of  the  Asiatic,  of  the  African,  in  British  Lepidoptera — 
Especially  prominent  in  the  female  ;  interpretation  of  pheno- 
menon— Affords  confirmation  of  theory  that  Mimicry  is 
produced  by  'natural  selection—"  External  conditions," 
"heredity" — An  explanation  of  sexual  difference  of  form 
and  colour — Mimetic  analogies  among  beetles — Hymenoptera 
mimicked  by  Lepidoptera,  Diptera,  Coleoptera,  Orthoptera, 
Hemiptera — Mimicry  of  Coleoptera — Of  ants  by  spiders — 
Of  vertebrates — Predaceous  insects  that  resemble  their  prey,  or 
a  form  to  which  their  prey  is  indifferent — The  great  frequency 
of  Mimicry  in  insects 242 

GLOSSARY  OF  SCIENTIFIC  TERMS 275 

INDEX 287 


LIST    OF    ILLUSTRATIONS 


Nest  of  a  Tree  Ant Frontispiece. 

Larva  of  the  Caddis-Fly  (Trichoptera) 7"itle-page. 

1.  Pupa  of  a  butterfly  (Pieris  brassiccz],  protected  by  a  hardened 

uniform  case 9 

2.  Pupa  of  a  Longicorn  Beetle  (Batocera  titana],  its  limbs  in 

separate  sheaths 1 1 

3.  A  honey-bearing  ant  (Myrmecocystus  mexicamts)  regurgitat- 

ing   honey  from    her   crop   at  the  solicitation  of  hungry 
workers 47 

4.  View  of  honey-bearers,  as  seen  in  natural  site,  clinging  to  the 

roof  of  a  honey-room .57 

5.  Profile  view  of  nest  of  a  Mining  Bee  (Andrena  vicina,  Smith), 

which  builds  her  nest  in  grassy  fields 72 

6.  Nest  of  an  Australian  Carpenter  Bee  (Lestis  bombylans]    .    .       77 

7.  Clay  nest  of  a  solitary  wasp  (Eiimenes),  in  early  stage,  from 

Natal 80 

8.  Pelopseus  Wasp  building  nest 85 

9.  Galls  of  Cynips  insana,  or  Dead  Sea  Apples 90 

10.   A  sack-bearing  caterpillar 96 

n.   Metura  Sander sii  from  Australia  (a  female) 97 

12.  Part  of  the  nest  of  a  trap-door  Spider  (Nemesia  eleanora]  with 

single  tube 105 

13.  Part  of  the  nest  oil  Nemesia  meridionalis  showing  the  surface- 

door  open,  and  the  lower  door  pushed  across  so  as  to  close 

the  principal  tube.    The  subsidiary  tube  ends  in  a  cul-de-sac    1 1 1 

14.  Nest  of  the  Turret  Spider  (Lycosa  arenicola] '114 


xiv  LIST  OF  ILLUSTRATIONS 

PAGE 

15.  Section  through  a  typical  nest  of  Formica 121 

1 6.  Section  through  the  nest  of  the  Leaf-cutting  Ant  CEcodoma 

cephalotes 125 

17.  Saiiba,  or  Leaf-cutting  Ant,  carrying  leaf 127 

1 8.  Large  flat  circular  disk  and  open  roads  of  the  Agricultural 

Ant  of  Texas  {Pogonomyrmex  barbatus]  made   above  the 
subterranean  formicary  . 131 

19.  Agricultural  Ants  cutting  down  obtruding  grass 132 

20.  Gravel  cone  nest  of  Honey  Ant,  built  partly  round  a  tuft  of 

gramma  grass 133 

21.  View  of  a  nest  of  a  Provident  Ant  (Attabarbara),  from  Men- 

tone,  showing  a  granary  excavated  in  rock,  and  the  conical 
refuse  heap ....     135 

22.  Fragment  taken  from  the  trunk  of  an  oak  inhabited  by  Fuli- 

ginous ants 139 

23.  Pseudomyrma  bicolor  inhabiting  Acacia  comigera 141 

24.  Nest  of  a  Tree  Ant  (CEcophylla  smaragdina)  from  India    .    .  145 

25.  Comb  of  a  small  Honey  Bee  (Apis floralis)  from  India   ...  155 

26.  Melipona  Bees  gathering  clay 158 

27.  Home  of  Vespa  nonuegica 159 

28.  Comb  of  Polistes  tepidus,  Fabr.,  with  central  pedicle     .    .    .  167 

29.  Comb  of  Polistes  canadensis,   Linn.,  inverted,   with   lateral 

support  and  irregular  cells,  many  still  containing  nymphs  .  167 

30.  Nest  of  Icaria  variegata 171 

31.  Nest  of  a  Brazilian  Wasp  (Apoica  pallidd) 174 

32.  Wasps'  nest  {Chartergus  apicalis\  from   Brazil,   interior  and 

exterior 185 

33.  View  of  exterior  of  nest  of  Myrapetra  scntellaris 194 

34.  View  of  interior  of  nest  of  Myrapetra  scutellaris 195 

35.  A    "stick-caterpillar"  (Ennomos  tiliaria),  which  in  colour, 

form,  and  attitude,  closely  resembles  a  twig  of  a  tree  upon 
which  it  lives 207 

36.  Caterpillar  of  Early  Thorn  Moth  (Selenia  illunaria)  showing 

supporting  thread  of  silk 210 

37.  Appearance  of  the  larva  of  Brimstone  Moth  (Rnmia  cratagata) 

when  seated  among  the  twigs  of  its  commonest  food-plant .    210 


LIST  OF  ILLUSTRATIONS  xv 

PAGE 

38.  The   hind   part  of   the    larva  of   Brimstone  Moth  (Rumia 

cratcegata),  seen  from  the  right,  showing  the  claspers,  and 
the  fleshy  projections  which  tend  to  fill  up  the  furrow 
between  the  larva  and  the  stem 211 

39.  Leaf  Butterfly  (Kallima)  in  flight  and  in  repose 213 

40.  A  "  Walking  Leaf"  Insect 217 

41.  A  "Walking-stick,"  or  Moss  Insect 219 

42.  Imitation  of  a  flower  by  a  Mantis  (Hymenopus  bicornis)  in 

active  pupa  stage 220 

43.  A  Bird's  excreta  mimicking  spider 228 

44.  Pupa   of    South   African    Swallow-tailed   Butterfly   (Papilio 

nireus]  attached  to  orange  -tree,  and  corresponding  in  colour 

to  its  deep-green  leaves 229 

45.  Pupa  of  Papilio  niretis  attached  to  woodwork,  the  colour  of 

which  it  imitates 229 

46.  The  larva  of  Peppered  Moth  (Amphidasis  betularia)  reared 

amid  green  twigs  and  leaves 236 

47.  The  larva  of  Peppered  Moth  reared  amid  dark-brown  twigs 

as  well  as  leaves 237 

48.  Larva  of  the  Buff- tip  Moth  (P.  bncephala\  a  caterpillar  with 

Warning  Colours  and  a  nauseous  taste 245 

49.  Hornet  and  Mimetic  Bug 249 

50.  An  Ant-like  Spider 254 

51.  An  Ant-like  Spider 255 

52.  Adult   caterpillar   of   the   Large  Elephant  Hawk  Moth  (C. 

elpenor)  when  undisturbed 256 

53.  Dorsal  view  of  the  caterpillar  of  the  Small  Elephant  Hawk 

Moth  (C.  porcellus]  in  its  alarming  attitude 257 

54.  The  larva  of  Puss  Moth  (Centra  vinula)  resting;  full-fed, 

natural  size 261 

55.  The  larva  of  Puss  Moth  in  its  terrifying  attitude 263 


ROMANCE  OF  THE  INSECT  WORLD 


NOTE. — An   asterisk   indicates   that  the   luord  so    marked  is 
mentioned  in  the  Glossary. 


CHAPTER  I 

METAMORPHOSES   OF   INSECTS 

Character  of  life-history  of  insects — Metamorphoses  of  the 
butterfly, beetles, &c. — "  Similarly-changing"  insects — The 
two  series  Heteromorpha  and  Homomorpha — True  meta- 
morphic  stages  considered  in  detail — egg — larva — shelters 
for  approaching  change — Meaning  of  pupa  and  other  terms 
applied  to  stage — Nature  of  condition  in  insects  which 
undergo  complete  metamorphoses — Signs  of  returning  life 
—Assumption  of  imago  state — Pseudo-imago — Subsequent 
career— Old  idea  of  metamorphoses — Modern  theory — 
Study  of  structures  implicated — External — Modifications 
of  internal  organs — Explanation  of  metamorphoses — 
Apparent  suddenness  of  changes— Of  the  death-like  period 
of  quiescence. 

IN  these  days  of  universal  education,  no  doubt  it 
would  prove  a  somewhat  hard  matter  to  discover  any 
number  of  persons  who  were  altogether  unacquainted 
with  the  wondrous  phases  of  insect  existence.  Many 
would  be  found  aware,  few  not,  that  during  the  period 

B 


2  ROMANCE  OF  THE  INSECT  WORLD     CHAP. 

of  their  life-history,  from  birth  to  infancy  and  on  to 
maturity,  the  great  majority  of  the  members  of  these 
little  lowly  winged  tribes  pass  through  a  series  of 
changes  of  condition,  and  assume  several  successive 
well-marked  forms,  to  all  appearances  totally  distinct 
the  one  from  the  other.  In  a  general  way  the 
youngest  persons,  and  the  most  ignorant,  are  in- 
formed of  the  fact,  but  how  many,  learned  and 
ignorant  and  young  alike,  ignore  it,  owing  to  the 
commonness  of  the  occurrences  and  the  minuteness 
of  the  objects,  and  thus  deprive  themselves  of  the 
exceeding  interest  and  pleasure  to  be  gained  from 
study  of  this,  which  is  perhaps  the  most  admirable  of 
all  the  extraordinary  pages  of  natural  history. 

The  butterfly,  whose  metamorphoses  are  so  striking 
to  the  young,  could  have  never  existed  as  we  now 
behold  it,  had  it  not  successfully  accomplished  a 
regular  series  of  changes  of  structure  since  the  day  of 
its  birth.  It  is  produced  by  the  parent  as  an  egg, 
from  which  it  is  hatched  in  the  shape  of  a  caterpillar 
or  larva,  a  worm-like  creature  of  soft  and  fleshy  con- 
sistence, furnished  with  a  mouth  and  a  few  short  legs, 
its  only  requirement  being  an  abundant  supply  of 
food.  Of  this  it  eats  with  an  incomparable  appetite, 
and  makes  haste  to  grow,  necessitating  repeated  casts 
of  skin.  Eventually  it  becomes  a  shrouded  chrysalis 
or  pupa.  This  sleep  being  over,  it  awakens  to  a  new 
life,  having  little  resemblance  to  its  old  condition, 
in  its  aspect,  or  internal  conformation,  or  in  the  work 
that  has  then  to  be  done, — a  winged  and  perfect 
butterfly.  In  the  case  of  beetles  likewise,  the  larvse 
or  grubs  at  their  emancipation  from  the  egg,  though 


I  METAMORPHOSES  OF  INSECTS  3 

they  differ  much,  are  all  more  or  less  in  an  immature 
stage.  Gradually  the  larvae  alter  to  the  quiescent 
pupae,  the  nymphs  so-called,  and  from  the  pupa 
emerges  the  perfect  beetle.  Bees,  wasps,  flies,  and 
many  more  undergo  similarly  marked  metamor- 
phoses. 

The  metamorphoses  of  some  insects,  however, 
are  far  less  decided,  as  in  the  grasshoppers,  locusts, 
crickets,  earwigs,  and  a  small  group  well-known 
to  gardeners  under  the  name  of  thrips.  In  these 
the  larvae  and  pupae  already  greatly  resemble  the 
fully-developed  parent.  The  changes  consist  prin- 
cipally in  a  gradual  increase  of  size,  with  casts  of 
skin,  and  as  pupae  the  insects  begin  to  show  signs 
of  the  acquisition  of  wings.  In  certain  cases  the  egg- 
stage  is  wanting,  the  larva  being  produced  alive, 
There  are  rare  anomalies  in  which  development  has 
been  carried  to  a  considerable  degree  before  birth. 

The  difference  in  the  nature  of  metamorphoses  has 
given  rise  to  a  simple  division  of  insects  into  two 
series  :  Heteromorpha,  according  to  Professor  West- 
wood,  or  those  in  which  there  is  no  resemblance 
between  the  parent  and  the  offspring  ;  and  Homo- 
morpha,  or  those  in  which  the  larva  resembles  the 
imago,  except  in  the  absence  of  wings.  In  the  former 
the  insects  may  be  said  to  undergo  complete  meta- 
morphoses ;  as  regards  the  latter,  their  metamorphoses 
are  incomplete. 

It  may  be  laid  down  as  a  universal  law  that  all  insects 
originate  from  eggs.  The  apparent  exceptions  com- 
prise the  few  instances  where  the  young  are  hatched,  or 
are  retained  within  the  body  of  the  mother.  The  varieties 

B  2 


4  ROMANCE  OF  THE  INSECT  WORLD     CHAP. 

of  eggs  it  is  almost  impossible  to  enumerate,  among 
the  butterfly  families  especially  scarcely  two  forms  are 
alike,  even  in  the  most  closely  allied  species   marked 
diversity  occurs.     They  may  be  round,  oval,*  oblong, 
pear-shaped,  lenticular,*    or    flattened    like    a    lens. 
Many  of  them  are   petiolated,*   or  placed  upon  foot- 
stalks, which  may  be  long  and  straight,  or  compara- 
tively  short   and    bent.     Others    are    provided   with 
particular  appendages  to  answer  various  ends.     They 
are   enriched  with   all    the   colours   of  the   rainbow, 
though   the   prevalent  hues   are   white,   yellow,  and 
green.     Sometimes  the  outer  coat  is  hard  and  firm, 
sometimes  it  is  a  mere  filmy  skin.     The  surface  may 
be    smooth    and    plain,   or    beautified   with   delicate 
sculptured    designs,   such    as    cross    lines    giving    a 
reticulated  *  appearance,  or  these  lines  may  be  curved, 
as  if  the  eggs  were  imbricated  *  or  covered  with  tiles  ; 
or   the   pattern    may   assume   the   form   of   decided 
knobs.     The  variation  in  external   shape,  markings, 
and  colour  is  not  greater  than   in  the  modes  of  dis- 
position of  the  eggs,  and  the  localities  where  they  are 
placed.     They  are  laid  singly  or  in  clusters,  and  for 
the  most  part  upon,  or  within,  or  near  the  substance, 
be  it  plant  or  animal,  which  will  serve  as  the  food  of 
the  larvae  that  will  presently  be  hatched  from  them. 
As  a  rule,  the  peculiarities  of  form  and  colour  bear 
relation    to    the    circumstances    of  disposition,    the 
objects   to   be   ensured    being  safety   from   external 
injury    and    the    proper   development   of    the    egg. 
Those  eggs  from   which  the  larvae  are  most  rapidly 
developed  require  the  aid  of  the  highest  temperature 
and  the  fullest  exposure  to   he  atmosphere. 


i  METAMORPHOSES  OF  INSECTS  5 

Usually  the  formation  of  the  larva  is  complete  soon 
after  the  egg  is  laid,  sometimes  the  process  lingers 
on  throughout  the  winter,  and  should  unfavourable 
circumstances  supervene,  it  is  surmised  that  it  may 
be  delayed  for  years.  Experiments  prove  that  eggs 
may  be  exposed  to  intense  cold,  such  indeed  as  to 
solidify  their  contents,  and  yet  remain  capable  of 
hatching.  The  growth  of  the  embryo  *  within  the 
egg  may  be  watched.  This  is  easily  perceptible  in 
the  case  of  a  transparent  egg,  by  holding  it  against 
the  light,  or  by  examining  it  through  a  strong 
magnifier.  Day  by  day  the  germ  steadily  increases 
from  a  tiny  speck,  until  it  is  too  large  for  the  egg  to 
contain,  and  it  breaks  through  the  now  tight  skin 
or  shell,  and  emerges  into  the  world  a  living  and 
active  being— the  grub  or  larva. 

The  word  larva  is  from  the  Latin,  and  signifies  a 
mask  or  phantom.  It  was  applied  by  the  great 
naturalist  Linnaeus  to  the  first  active  stage  of 
insects,  with  the  idea  that  during  its  continuance 
the  glories  of  the  future  perfect  creature  were, 
as  it  were,  masked  or  shadowed  out.  Unhappily 
there  is  no  corresponding  general  term  in  English. 
The  larvae  of  moths  and  butterflies,  which  are 
coloured  and  often  hairy,  are  spoken  of  as  cater- 
pillars. White  fleshy  and  more  compact  larvae, 
legless,  or  possessed  of  legs,  as  those  of  many  beetles 
and  flies,  are  commonly  known  as  grubs  and  maggots. 
Such  as  resemble  the  parent,  as  a  rule  are  designated 
by  the  parent's  name. 

It  is  interesting  to  follow  the  life-history  of  an 
insect  that  is  subject  to  true  metamorphoses.  From 


6  ROMANCE  OF  THE  INSECT  WORLD     CHAP. 

the  moment  of  its  liberation  from  the  egg  as  a  larva* 
until  it  assumes  the  perfect  form,  its  life  is  one 
continuous  succession  of  changes.  These  are  not 
merely  from  larva  to  pupa,  and  from  pupa  to  perfect 
insect,  for  even  while  it  is  a  larva  it  undergoes  a 
series  of  sheddings  of  skin,  or  moults  as  they  are 
called,  previous  to  its  attainment  of  its  full  size  and 
growth.  No  sooner  is  a  caterpillar  hatched  than  it 
begins  eating,  its  first  meal  often  consisting  of  its 
discarded  egg-shell.  Perhaps  this  dainty  morsel 
tempts  the  appetite,  at  any  rate  the  hunger  that  the 
insect  displays,  and  the  amount  of  food  that  it 
requires  to  satisfy  it  are  something  wonderful. 
Naturally  it  increases  immensely,  and  the  skin  has 
to  stretch  to  allow  of  the  greater  bulk.  By  and  by 
there  comes  a  day  when  the  skin  will  extend  no 
more,  it  cracks,  and  the  larva  crawls  forth,  clad  in 
a  bright  new  coat.  The  process  evidently  produces 
the  greatest  discomfort  and  uneasiness.  A  few  hours 
before  the  divestment  begins  the  larva  ceases  to  eat, 
and  remains  motionless,  meanwhile  the  body  suffers 
powerful  twitchings  and  contractions.  But  when 
once  the  skin  yields — it  splits  down  the  back — the 
actual  withdrawal  from  the  clothing  is  seldom  of 
long  duration.  The  external  covering  of  the  body  is 
not  the  only  thing  that  is  cast.  The  whole  internal 
lining  of  the  mouth  and  the  digestive  canal,  and  that 
of  the  respiratory  organs  are  likewise  detached  and 
come  away  with  the  skin.  This  change,  though  it  is 
most  conspicuous  at  the  last  moult  of  the  larva, 
probably  takes  place  at  the  occurrence  of  each 
shedding. 


I  METAMORPHOSES  OF  INSECTS  7 

After  the  operation,  the  creature  is  soft  and 
languid,  and  pauses  to  recover  from  its  exertions. 
Then  it  begins  nibbling  and  devouring  with  increased 
voracity,  since  its  digestive  organs  are  now  more 
capacious.  Some  insects  make  a  fresh  start  with 
their  old  skin,  but  many  at  once  remove  to  new 
feeding-grounds.  Soon  further  enlargement  necessi- 
tates a  second  change.  The  moults*  vary  in  frequency 
in  different  species ;  in  general  they  occur  about 
three  times,  or  oftener.  Usually  the  first  takes  place 
about  the  twelfth  day,  the  second  after  the  further 
lapse  of  a  week,  the  third  happens  six  or  eight  days 
later  still,  the  power  of  consumption  of  food  at  each 
moult  being  augmented. 

Sphinx  ligustri,  the  Privet  Hawk  Moth,  is  known  to 
increase  at  the  rate  of  over  11,000  times  its  original 
weight  in  the  space  of  thirty-two  days,  a  pro- 
portion, great  as  it  is,  largely  exceeded  by  the 
goat  moth,  which  increases  to  the  amount  of  no 
less  than  72,000  times  its  first  weight,  but  this 
larva  is  very  long-lived.  Reason  for  the  immense 
storage  of  food  is  found  in  the  fact  that  all  growth  is 
effected  in  the  larva  and  pupa  stages,  for  when  the 
insect  becomes  perfect  it  alters  no  more.  The  pupa* 
period  is  not  only  a  state  of  death-like  sleep,  during 
which  no  food  can  be  taken,  it  is  the  time  when 
occurs  the  most  rapid  development  of  the  tissues  of 
the  body.  The  nourishment  accumulated  by  the 
larva  has  to  admit  of  these  alterations,  and  has  like- 
wise perhaps  to  serve  as  an  immediate  source  of 
nutriment  to  the  insect  on  its  awakening  at  the  end 
of  the  important  pupa  season. 


ROMANCE  OF  THE  INSECT  WORLD     CHAP. 

In  some  cases  the  duration  of  larval  life  extends 
over  one,  two,  or  even  five  years.  In  all  species  it  is 
much  influenced  by  the  weather  and  other  circum- 
stances, for  cold  as  a  rule  retards  growth  and  warmth 
hastens  it.  Many  larvae  have  an  almost  unlimited 
power  of  endurance  of  cold,  and  may  be  frozen  hard 
without  the  slightest  injury.  That  a  severe  winter  is 
highly  beneficial  for  the  crops  in  precluding  proba- 
bility of  insect  attack  in  the  following  spring  is  utter 
fallacy.  But  though  larvae  will  bear  great  cold,  they 
are  extremely  susceptible  to  over-supply  of  moisture, 
whether  from  rain  or  from  dampness  of  food,  a 
characteristic  worthy  of  consideration  when  attempt- 
ing to  exterminate  an  insect  pest. 

Suppose  that  an  insect  is  near  the  completion  of 
its  term  of  growth,  when  for  the  last  time  as  a  larva 
it  will  cast  its  coat,  and  will  emerge  therefrom  in  the 
next  stage  of  its  existence — a  pupa.  Great  changes 
in  its  internal  organs  since  its  exclusion  from  the  egg 
are  beginning  to  take  place,  and  greater  ones  are  yet 
to  come.  As  before  its  previous  but  less  momentous 
larval  skin-sheddings,  it  seems  to  suffer  inconvenience, 
it  becomes  exceedingly  restless  and  irritable,  it 
neglects  food  and  diminishes  in  weight,  and,  as  if 
aware  of  its  distressing  delicacy  and  defencelessness 
when  the  skin  is  abandoned,  as  a  rule  it  makes  haste 
to  seek  or  construct  some  shelter  with  care  and  con- 
sideration, where,  secure  from  harm,  the  otherwise 
disastrous  revolution  may  be  effected,  and  the  hapless 
stage  of  pupal  life  may  be  lived  through.  Many 
species,  like  the  silk-worm  caterpillar,  secrete  and 
draw  a  gummy  fluid  from  their  mouths,  and  spin  a 


METAMORPHOSES  OF  INSECTS 


cosy  silken  nest  or  covering  around  them,  known  as 
the  cocoon  ;*  occasionally  the  silk  is  mingled  with 
particles  of  wood  or  earth.  Some  of  the  butterflies 
simply  suspend  themselves  vertically  by  their  hinder- 
most  legs,  head  downwards,  or  they  carry  a  silken 
cable  across  their  body  to  keep  them  from  falling, 
affixing  the  girdle  to  the  under-surface  of  an  object 
such  as  a  leaf  or  twig.  Many  insects  hollow 
out  a  cell  or  cavity  in  the  ground  and 
line  it  with  web  of  silken  material.  The 
larva  being  duly  prepared,  after  a  short 
repose  its  skin  splits,  and  with  infinite 
shuffling  and  wriggling  is  thrown  off,  and 
then  the  insect  is  known  as  a  pupa.  In 
the  true  flies  the  outer  skin  of  the  full- 
grown  larva  is  not  shed,  the  maggot 
contracts,  while  the  skin  gradually  hard- 
ens, assuming  the  appearance  of  an  oval 
brownish  shell  or  case,  which  serves  the 
same  purpose  as  a  cocoon  and  affords  an 
admirable  protection  to  the  insect  which 
changes  to  pupa  inside. 

•-pi        «      •  ,1  •       *i_      i      •     i   j       brassic(e)  protect- 

The  being  that  emerges    in  its  bright    ed  by  a  hardened 

i .  rr  c  11  uniform  case,   se- 

new  coat  is  very  different  from  the  larva,    creted   from  the 

-  ,  .          -  111  pores  of  the  insect. 

tor  the  muscles  have  already  shortened 
and  enlarged  in  certain  parts,  so  modifying  the 
simple  worm-like  form  that  the  entire  shape  and 
limbs  of  the  future  perfect  creature  are  apparent, 
and  the  wings,  though  they  are  very  small  and  in 
rudimentary  condition,  may  be  plainly  traced.  The 
new  pupa,  should  it  be  that  of  a  butterfly  (see  Fig. 
i),  as  of  Sphinx,  having  got  rid  of  its  larval  skin, 


io  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

hangs  for  a  few  seconds  at  rest.  It  suffers  some  powerful 
contractions  and  alterations,  and  the  wings  become 
much  enlarged  ;  moreover,  a  very  transparent  fluid 
secreted  from  the  pores  which  facilitated  the  slipping 
off  of  the '  discarded  skin,  is  now  diffused  over  the 
whole  body,  and  as  the  insect  sinks  into  quiescence, 
dries  and  hardens  into  a  compact  protective  covering, 
uniting  and  supporting  the  tender  and  erstwhile 
separate  limbs. 

To  the  pupa  the  terms  nymph,  chrysalis,  and 
aurelia  are  also  given.  The  two  latter  names  were 
used  by  the  older  entomologists,  the  first  by  the 
Greeks,  the  second  by  the  Romans,  for  this  stage 
of  transformation  in  the  butterflies  and  moths, 
being  expressive  of  the  glittering  golden  colours 
or  spots  with  which  many  pupae  of  butterflies  are 
adorned.  '  Nymph  '  is  applicable  only  to  those  pupae 
in  which  the  limbs  remain  free  in  separate  mem- 
branous skin-sheaths,  folded  beneath  the  breast  and 
body  (see  Fig.  2),  as  in  many  of  the  beetle  and  bee 
tribes,  unlike  the  common  uniform  covering  of  Lepi- 
doptera.  At  present  the  term  is  usually  confined  to 
active  Homomorphic  insects  when  in  this  stage.  The 
word  pupa  itself,  meaning  an  infant,  was  adopted  by 
Linnaeus  as  a  general  term  for  the  period.  It  is 
peculiarly  appropriate,  for  insects  in  this  state  are 
approaching  their  completion,  but  are  not  fully  deve- 
loped, either  in  their  limbs  or  functions,  and  in  many 
cases  recall  the  condition  of  a  child  swathed  or  bound 
up  as  in  barbaric  fashion.  The  pupae  of  flies,  where 
the  insect  is  enclosed  within  the  smooth  uniform  case 
formed  of  its  own  cast  larval  skin,  but  no  limbs 


METAMORPHOSES  OF  INSECTS 


ii 


and  other  parts  of  the  body  are  visible  externally,  is 
called  'coarctate.'* 

In  insects  which  undergo  complete  metamorphoses 
the  pupa  is  a  most  remarkable  and  characteristic 
condition.  Almost  as  long  as  the  state  continues, 
the  insect  usually  lies  quiescent,  capable  of  only  the 
faintest  motion  when  touch- 
ed, in  a  seeming  deathlike 
torpor,  tasting  no  food,  and 
the  vast  change  which  was 
beginning  when  in  many 
instances  the  larva  took 
shelter  is  gradually  com- 
pleted, incapacitating  the 
creature  for  a  continuance 
of  its  previous  life,  while 
adapting  it  for  life  in  the 
future.  It  is  no  wonder  that 
the  period  of  such  organic 
evolution  is  at  the  same 
time  one  of  great  functional 
inaction,  which  lasts  longer 
than  the  rest  succeeding  -—  n 

FIG.   2.  —  Pupa  of  a  longicprn  beetle 

each     minor     Skin-Shedding     (Batocera  titana\  its  limbs  in  separate 

°      sheaths  folded  beneath  the  breast  and 

that  has  gone  before.     Res-  body- 

piration  and  circulation,  for  instance,  are  reduced  to  a 
minimum.  Some  insects  remain  in  pupa  for  a 
very  long  time,  particularly  true  of  the  Sphinx 
moths,  which  often  continue  in  chrysalis  for  nine 
months  of  the  year.  But  on  the  other  hand,  as 
regards  ants  and  bees  and  many  others,  it  is  the 
shortest  period  of  all,  and  occupies  little  more  than  a 


12  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

week  or  ten  days.  In  every  species  the  length  is 
much  affected  by  the  weather.  Should  a  butterfly 
larva  turn  to  pupa  during  the  summer,  it  may 
become  perfect  in  eight  or  ten  days,  but  if  it  reach 
the  chrysalis  state  at  the  approach  of  winter  the 
change  to  butterfly  may  be  delayed  for  months,  until 
development  is  quickened  by  the  warmth  of  returning 
spring.  Reaumur  discovered  that  if  a  chrysalis  were 
deposited  in  an  ice-house,  further  transformation 
might  be  retarded  for  two  or  three  years.  If  one 
deep  in  its  winter  sleep  were  brought  in  from  the 
cold  to  great  heat,  the  final  metamorphosis  might 
take  place  in  ten  or  fourteen  days. 

As  the  structures  become  completed,  and  the  hour 
for  entering  the  imago  condition  draws  near,  the 
immobile  pupa  begins  to  show  signs  of  returning  life. 
In  Sphinx  respiration  increases  rapidly,  twitchings 
and  contortions  indicate  what  is  about  to  occur,  and 
the  form  of  the  coming  insect  becomes  more  and 
more  apparent.  In  every  instance  the  assumption  of 
the  perfect  state  is  accompanied  by  a  casting  of 
the  outer  skin.  Before  this  can  be  effected,  many 
insects  have  first  to  acquire  the  power  of  locomotion. 
Caddis  flies  which  undergo  their  previous  metamor- 
phoses in  water,  must  be  able  to  come  to  the  sur- 
face, or  to  quit  an  element  in  which  they  cannot 
now  exist.  Pupae  that  are  lodged  in  the  interior 
of  trunks  of  trees,  or  in  crop  stems,  or  beneath  the 
ground,  usually  issue  forth  from  these  situations  ; 
and  many  Lepidoptera  and  others  have  to  struggle 
through  silken  wrappings.  Having  overcome  the 
obstacles  that  oppose  its  escape,  the  pupa  bursts 


I  METAMORPHOSES  .OF  INSECTS  13 

its  covering,  and  the  insect  emerges  perfect  in  all  its 
parts.  Sometimes  a  little  while  elapses  ere  it  takes 
to  flight.  The  wings  of  butterflies  and  moths  are 
somewhat  drooping  and  difficult  to  spread,  and  the 
body  is  humid  and  soft.  After  considerable  res- 
piratory effort,  and  a  rest,  and  exposure  to  the 
drying  influence  of  the  atmosphere,  the  imago  gains 
strength  and  solidity,  its  wings  enlarge  and  expand, 
and  at  last  it  enters  on  its  higher  career  and  the 
delight  of  finished  faculties.  Humble  bees  do  not  at 
once  come  abroad  to  the  outer  air  in  their  new  dress. 
Their  bodies  are  excessively  moist  and  weak  when 
they  emerge  from  the  cells,  and  their  hairs  are  of 
a  whitish  gray.  They  crowd  together  in  the  nest, 
and  seem  to  feel  the  chill  of  diminished  warmth.  In 
a  few  hours  the  susceptibility  vanishes,  and  the 
proper  colours  are  acquired,  but  the  bees  are  not 
vigorous  or  capable  of  great  exertion  until  the 
following  day. 

When  an  insect  has  withdrawn  from  the  pupal  case 
it  is  perfect  in  form,  its  internal  organs  are  perfect,  and 
metamorphoses  are  now  concluded.  An  apparent 
exception  to  the  rule  occurs  in  the  case  of  the  May- 
flies (Ephemerae).*  The  pupae  creep  out  of  the 
water,  and  perform  the  feat  of  getting  rid  of  the 
pupal  covering,  their  wings  expand,  and  they  take 
feebly  to  flight.  Shortly  however  they  settle  again, 
and  having  shed  an  extremely  delicate  skin,  re- 
new their  aerial  excursions  with  redoubled  energy. 
The  condition  previous  to  the  final  moult  has  been 
called  the  pseudo-imago. 

Metamorphoses  being   over,   the   task  for   the  re- 


H  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

mainder  of  life,  which  is  often  an  ephemeral  span,  is 
to  propagate  the  kind.  Numerous  adults  perform  this 
work  unhindered  by  any  other  desire,  even  that  of 
partaking  of  food.  The  female  lays  her  eggs,  and 
then  (usually)  dies,  and  so  the  cycle  of  existence  is 
complete.  Many  an  insect  lives  merely  one  short 
year.  Generally  speaking,  it  is  in  summer  or  autumn 
that  the  parent  produces  the  eggs,  which  quickly 
hatch,  and  in  the  state  of  larvae,  or  more  usually 
pupae,  the  young  hybernate,  or  sleep  in  shelter  during 
the  winter,  and  become  perfect  in  the  following  spring. 
The  mother  seldom  long  survives  the  laying  of  her. 
eggs-  However,  these  points  are  liable  to  much 
variation,  according  to  the  seasons  and  the  different 
species. 

The  term  metamorphoses  or  transformations  which 
is  applied  to  these  changes  that  insects  undergo  as 
life  proceeds,  before  they  arrive  at  their  perfect  state, 
is  at  first  maybe  a  little  misleading.  From  the 
earliest  times  civilised  nations  have  produced  students 
of  nature  who  have  marvelled  at,  and  watched,  and 
endeavoured  to  explain  these  strange  alterations. 
The  old  ideas  on  the  subject  were  wide  of  the 
truth.  It  was  believed  there  took  place  a  complete 
transformation  of  one  being  into  another — a  trans- 
formation as  startling  as  though  a  serpent  turned  to 
a  bird — and  that  the*  most  singular  poetic  by- 
gone fables  of  metamorphoses  were  repeated  in  the 
case  of  insects.  Modern  research,  aided  by  the 
microscope,  has  proved  this  opinion  to  be  incorrect. 
These  transformations  are  so  many  stages  or  seem- 
ing pauses  in  the  natural  course  of  a  progressive 


I  METAMORPHOSES  OF  INSECTS  15 

development  or  evolution  of  the  one  self-same  animal. 
The  caterpillar  in  the  egg  is  already  possessed  of  the 
principal  vital  organs,  which  have  to  be  modified  and 
perfected  ;  others  appear  later  on  ;  and  often  early- 
existing  structures  die  away  as  growth  advances. 
Nothing  will  more  plainly  show  the  fact  that  meta- 
morphoses are  but  a  progressive  development  of  the 
immature  into  the  mature  being  than  a  brief  examina- 
tion of  some  of  the  structures  which  are  altered,  and 
of  those  which  put  in  their  appearance  during  the 
successive  stages  of  life. 

An  insect  may  be  broadly  defined  as  an  animal 
that  is  formed  of  a  series  of  rings  or  segments.*  They 
can  be  traced  in  the  embryo  within  the  egg,  they  are 
seen  plainly  in  the  larva,  and  can  be  distinguished  in 
the  perfect  insect.  The  normal  number  of  distinct  rings 
in  all  insects  is  probably  thirteen.  The  first  consti- 
tutes the  head.  In  most  larvae  the  remaining  twelve 
are  equally  developed  and  differ  little  from  each 
other  in  general  appearance.  But  an  imago  is 
evidently  distinctly  divisible  into  three  pieces — the 
head,  the  body  or  thorax,  and  the  abdomen.  How- 
ever greatly  the  forms  of  these  regions  may  vary,  the 
difference  is  simply  due  in  each  case  to  greater  or 
less  development  of  the  primary  segments,  and  in 
many  cases  the  various  segments  can  be  satisfac- 
torily numbered  and  recognised.  A  difficulty  lies 
in  the  fact  that  the  changes  are  not  brought  about 
by  alteration  in  the  consistence  of  the  integu- 
ments only,  but  by  the  union  of  several  segments 
into  one  or  more  separate  consolidated  portions,  and 
by  the  greater  or  less  retraction  of  segments,  each 


16  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

within  tlje  one  which  immediately  precedes  it.  Thus 
their  number  becomes  diminished,  yet  a  segment 
never  entirely  disappears,  but  invariably  leaves 
trace,  however  faint,  of  its  former  distinction.  So 
far  as  can  be  ascertained,  the  second,  third,  and 
fourth  rings  of  the  larva  go  to  form  the  thorax  of 
the  perfect  insect,  the  remaining  nine  constitute  its 
abdomen.  The  fifth  however  enters  in  part  into  the 
composition  of  the  thorax  and  forms  the  connection 
of  that  portion  with  the  abdominal  region.  It  is 
frequently  atrophied,*  and  has  almost  entirely  disap- 
peared. If  this  piece  be  excluded,  the  abdomen  is 
composed  of  eight  segments.  Any  deviation  from 
the  rule  in  regard  to  reduced  numbers  will  be  found 
to  be  apparent  and  not  real. 

The  larvae  of  some  insects  are  entirely  destitute  of 
legs  and  feet,  as  in  the  bee  family  and  among  flies, 
and  the  body  is  otherwise  modified  where  power  of 
locomotion  is  required.  Many  larvae,  however,  possess 
pedal*  appendages  of  two  classes.  These  are  true 
legs,  six  in  number,  arranged  in  pairs,  always  on  the 
three  segments  of  the  thorax.  So-called  false  or 
abdominal  legs  are  attached  to  the  segments  of 
the  .abdomen,  their  number  ranging  from  a  single 
couple  even  to  eight  pairs.  The  true  or  thoracic 
legs  of  young  insects  are  very  small  and  scale-like, 
and  are  distinguished  from  the  false  legs  by  distinct 
articulations  or  joints,  by  their  strength  and  firmness 
of  texture,  and  their  general  pointed  form.  The 
whole  of  these  thoracic  legs  in  all  larvae  that  possess 
them  are  nearly  equally  developed.  In  structure 
and  appearance  the  false  legs  are  totally  different. 


I  METAMORPHOSES  OF  INSECTS  17 

They  are  soft  and  membranous,*  and  their  forma- 
tion is  often  exceedingly  curious  ;   in  every  instance 
they  are  only  processes*  of  the  exterior  covering  of 
the  insect.     But  the  difference  between  the  two  kinds 
which  must  be  particularly  pointed  out  is  this.     The 
true   legs    are   those   which    enlarge    and    otherwise 
develop  into  the  limbs  of  the  future  imago,  whatever 
be   their   size    or  variety  of    form,   whereas   the  ab- 
dominal legs  are  not  persistent,*  but  are  lost  with 
the  cast  skin  during  the  metamorphosis  of  the  larva 
into  chrysalis.     Here  then  is  a  clue  admitting  of  the 
recognition  with  certainty  of  the  individual  segments 
that  compose  the  thorax,  however  much  the  distinc- 
tion between  them  may  have  become  obliterated  in 
course   of  development.     Each   pair  of  legs  in  the 
perfect  insect  answers  to  each  pair  of  true  legs  in  the 
larva. 

In  the  case  of  larvae  that  are  destitute  of  true  legs, 
these  wonderful  organs  have  to  be  developed  with  all 
their  muscles  and  nerves  during  metamorphoses. 

The  thorax,*  which  thus  gives  origin  to  the  legs,  is 
usually  large,  and  the  union  of  the  segments  is  firm 
in  proportion  to  the  rest  of  the  body.  On  the  size  of 
these  segments  and  their  consolidation  greatly  de- 
pends the  strength  of  the  insect.  This  region  also 
supports  the  wings  ;  to  be  precise,  these  appendages 
are  attached  to  the  two  hinder  segments,  the 
meso*-  and  meta*-thorax.  The  development  of  the 
thorax  is  not  surprising,  for  there  must  be  abun- 
dant space  within  for  the  muscles  which  move  the 
organs  for  walking  and  for  flight.  There  is  little 
trace  of  wings  in  the  caterpillar,  so  that  the  formation 

C 


i8  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

of  these  organs — as  is  mainly  the  case  with  the  legs — 
may  be  said  to  occur  during  the  pupal  period  of  rest. 
It  follows  that  the  great  enlargement  of  the  thorax 
as  seen  in  the  perfect  insect  does  not  generally  take 
place  until  the  chrysalis  life  has  progressed. 

The  wonderful  and  delicate  organ  called  a  wing 
is,  to  all  appearances,  composed  of  a  simple  mem- 
brane.* In  reality  it  is  double ;  and  between 
the  two  tissues  a  multitude  of  minute  air-vessels 
ramify  through  every  part,  accompanied  by  canals 
or  passages  for  the  circulatory  fluids.  Imme- 
diately after  the  assumption  of  the  perfect  state 
these  tracheae  become  solidified  like  the  rest  of  the 
skeleton.  They  are  hollow  for  the  reception  of  air, 
and  afford  strength  and  lightness  to  the  wings,  the 
motions  of  which  are  intimately  connected  with  the 
function  of  respiration.  The  membranes  are  con- 
tinuous with  and  expanded  portions  of  the  common 
tegument  *  of  the  sides  of  the  segments  of  the 
thorax.  Their  surfaces  may  be  transparent,  or 
coated  with  dusty  scales  of  microscopic  size.  The 
distribution  of  the  contained  tracheae,  or  neuration,* 
and  the  appendages,  though  of  the  highest  intrinsic 
interest,  are  outside  the  present  subject. 

The  abdomen,*  the  third  division  of  the  body  of 
an  insect,  is  the  seat  of  the  greater  part  of  the 
digestive  organs,  the  respiratory  and  circulatory, 
and  the  generative  systems. 

The  head  of  some  larvae,tlike  "the"  rest^of  the  divi- 
sions of  the  body,  is  covered  with]  soft;  flexible  skin. 
Usually  it  is  rounded  or  oval  in  form  and  of  harder 
texture  than  the  other  segments.  Three  great  pairs 


I  METAMORPHOSES  OF  INSECTS  19 

of  attached  organs,  the  mouth  organs,  are  situated  at 
its  inferior  surface,  and  at  the  lateral  and  anterior 
surfaces  it  carries  the  rudiments  of  antennae,*  or 
feelers,  and  the  eyes  where  they  are  present.  In 
the  perfect  insect,  the  number  and  position  of  these 
parts  are  precisely  similar.  It  is  only  in  a  manner 
true  to  say  that  the  head  of  an  insect  is  composed 
of  one  segment.  For  though  at  the  birth  of  the 
larva  no  satisfactory  separation  of  this  portion  into 
segments  can  be  detected,  it  is  a  fact  that  it,  like 
the  other  regions,  is  made  up  of  several  rings. 
The  exact  number  which  enter  into  its  com- 
position has  not  yet  been  made  absolutely  clear. 
Probably  the  head  appendages  which  form  part 
of  the  organs  of  manducation  are  the  proper 
articulated  members  of  distinct  rings,  and  are 
analogous  to  those  which  constitute  the  locomo- 
tive organs  of  the  body.  Since  each  pair  of  the 
latter  is  attached  to  a  particular  segment,  in  the  same 
manner  it  may  be  presumed  that  the  mouth-parts  were 
attached,  indicating  an  early  separation  of  the  head* 
into  three  segments.  Probably  there  were  four, 
and  perhaps  five.  In  many  larvae  a  projecting  papilla, 
the  spinneret,  is  situated  within  the  mouth.  It  opens 
into  the  glands  that  secrete  the  silken  material  with 
which  the  owner  spins  its  cocoon,  and  performs 
similar  tasks.  It  is  an  organ — its  function  being  no 
longer  needed — that  dies  ere  the  insect  reaches  its 
perfect  stage.  While  still  in  the  glands,  silk  is  a 
thickish  viscous  *  fluid.  When  about  to  make  use  of 
it  the  larva  places  the  spinneret  in  contact  with  some 
object,  and  quickly  withdraws  it,  at  the  same  time 

C  2 


20  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

exuding  a  drop.  The  silk  immediately  hardens 
on  exposure  to  the  air,  and  is  drawn  out  into 
threads  equally  remarkable  for  fineness  as  for 
strength. 

In  the  perfect  state  of  insects  the  skin  may  be 
tough  and  thick,  but  still  flexible  ;  while  in  the  case 
of  the  beetle  it  is  so  dense  and  hard  as  to  appear 
like  horn.  But  though  the  variation  is  great,  this 
tissue  is  invariably  composed  of  a  peculiar  substance 
called  chitine.  It  is  formed  of  two  layers,  an  inner 
one  which  is  soft,  and  not  made  up  of  chitine — the 
true  skin  ;  the  other  is  external  and  superficial — the 
epidermis,*  which  is  capable  of  becoming  hard  and 
horny.  Both  are  intimately  connected.  It  is  the 
epidermis  that  is  cast  at  the  transformations.  From 
its  inner  layers  the  new  skin  is  developed,  and 
peels  away  as  it  were  from  the  outer  ones,  when  the 
latter  soon  dry  and  become  shrivelled  and  are 
thrown  off,  and  the  new  skin  eventually  clothes  it- 
self with  a  fresh  epidermis.  Newport  infers  that 
chitine,*  the  basis  of  the  insect  skeleton,  is  inter- 
mediate in  its  chemical  condition  between  the  bony 
and  dermal  structures.  In  other  words,  it  is  bony 
matter  imperfectly  developed,  so  modified  that  while 
it  affords  the  animal  strength  and  solidity,  it  at 
the  same  time  admits  of  the  performance  of  all  the 
organic  functions  of  the  true  skin.  And  it  may 
be  that  its  exuviation*  is  due  not  only  to  the 
continuous  growth  of  the  insect,  which  causes  the 
body  to  become  too  large  for  the  covering  to  contain 
but  to  changes  in  the  actual  condition  of  the  skeleton* 
itself,  dependent  upon  the  same  laws  of  existence 


I  METAMORPHOSES  OF  INSECTS  21 

which  regulate  the  removal  of  the  old  and  the  deposi- 
tion of  new  matter  in  the  bones  and  other  structures 
of  vertebrates.1 

The  modifications  of  the  outsides  are  not  more 
remarkable  than  the  changes  that  take  place  in 
the  internal  organs  during  progressive  development. 
Many  persons  do  not  think  that  a  larva  has  any 
internal  organs  at  all.  They  hold  the  opinion  of 
the  gentleman  who  once  confessed  his  belief  to  the 
well-known  naturalist,  the  late  Mr.  Wood,  that  a 
caterpillar  is  "  nothing  but  skin  and  squash."  In 
fact,  larvae  live  only  for  eating,  so  that  their 
inward  arrangements  consist  almost  entirely  of 
the  digestive  system,  which  in  many  is  scarcely 
more  than  an  elongated  tube  or  sac  very  much 
dilated,  serving  as  a  most  capacious  stomach.  As 
such  it  exists  in  the  apodous  *  larvae  of  some 
of  the  bee  family.  In  other  members  of  the  order 
it  is  more  complicated,  and  it  would  be  pos- 
sible to  go  through  a  list  of  larvae  whose  digestive 
organs  gradually  rise  in  the  scale  of  importance, 
until  they  become  fairly  developed  and  the  simple 
tube  begins  to  assume  the  intricacies  that  it  possesses 
in  perfect  insects.  Turning  to  the  latter,  the  form 
of  the  system  is  not  more  indicatory  of  the  habits 
of  the  species  than  in  larvae.  Regarding  it  in  a 
general  way,  the  alimentary  canal  becomes  a  long 
convoluted  organ,  and  shows  certain  swellings  and 
constrictions,  which  mark  its  division  into  several 
compartments.  Each  exhibits  distinct  difference 
of  texture  and  is  adapted  to  peculiar  function, 

1  Newport. 


22  ROMANCE  OF  THE  INSECT  WORLD      CHAf. 

though  all  are  subservient  to  the  one  end,  the  assimi- 
lation of  food  into  matter  fitted  for  nutrition.*  New 
structures  are  likewise  added  of  which  formerly  there 
was  no  appearance.  Taking  the  principal  parts 
of  the  tube  in  their  order  of  succession  from  the  mouth, 
with  which  the  digestive  structures  are  continuous,  an 
oesophagus,  or  gullet,  a  stomach,  and  a  small  and 
large  intestine  may  be  distinguished.  Glandular 
appendages  complete  the  apparatus. 

Food  passes  from  the  mouth  into  the  gullet,  or 
oesophagus,*  a  portion  of  the  tube  that  runs  through 
the  thorax  in  a  straight  line.  In  the  case  of  insects 
that  live  on  fluids  it  is  usually  narrow,  when  the  diet 
is  more  or  less  solid  it  becomes  comparatively  wide 
and  strong.  A  dilation  of  the  gullet,  called  the  crop, 
is  often  present,  where  food  may  be  stored  for  a 
time  previous  to  digestion.  This  is  a  provision 
common  in  gross  feeders,  such  as  grasshoppers  and 
locusts,  and  in  those  that  provide  for  the  wants 
of  their  young.  From  the  crop  the  bee  disgorges  its 
gathered  honey  into  the  cells  of  the  comb  by  means 
of  the  muscular  coats  of  the  reservoir.  A  valve  *  cuts 
off  the  membranous  bag  from  the  true  stomach,  and 
must  effectually  prevent  all  regurgitation  *  from  the 
latter  into  the  former.  In  butterflies,  and  occasionally 
in  flies,  the  crop  is  rather  more  separated  from  the 
gullet,  and  opens  into  it  by  a  tube  or  neck.  The 
stomach,  the  principal  organ  of  digestion,  varies  much 
in  length  and  in  size  generally.  Here  the  food  is 
mixed  with  the  gastric  juice,  and  is  finally  converted 
into  chyme,  just  as  in  ourselves  and  the  higher 
animals.  As  in  man,  the  secretion  depends  upon  the 


I  METAMORPHOSES  OF  INSECTS  23 

state  of  the  stomach,  whether  it  is  filled  or  not. 
When  the  stomach  is  empty  the  juice  is  not  secreted, 
upon  the  introduction  of  food  the  glands  secrete 
actively,  and  the  juice  becomes  acid.  Obviously  the 
secretion  must  be  almost  continuous  during  the  life- 
time of  a  larva,  which  seldom  ceases  to  eat.  But 
as  the  perfect  stage  is  approached,  the  glands  are 
atrophied  and  dwindle  away,  and  sometimes  become 
altogether  obscure.  Their  development  is  best  in 
animal  feeders  ;  in  herbivorous  insects  they  are  much 
less  conspicuous.  The  modifications  of  the  intestines 
are  of  less  consequence  than  those  of  the  other 
parts.  Salivary  glands  are  situated  one  on  each 
side  of  the  oesophagus,  and  provide  saliva*  to  mingle 
with  and  lubricate  food  in  the  mouth,  and  to  assist 
in  its  digestion.  They  are  largely  developed  in 
Lepidopterous  larvae,  in  which  they  form  the  web- 
spinning  apparatus  and  secrete  silk.  When  the  cater- 
pillar has  completed  its  cocoon,  and  turns  to  chrys- 
alis, there  is  no  further  need  of  silk.  Consequently 
the  glands  become  small,  and  their  function  is 
altered. 

At  first  sight  nothing  could  be  more  astonishing 
than  the  difference  in  the  nervous  system,  as  regards 
the  size  and  relative  position  of  its  parts,  at  the  various 
stages  of  development.  A  minute  examination  before 
and  after  metamorphoses  reveals  that  it  undergoes 
no  perfect  alteration  of  plan.  The  nervous  system 
of  the  larva  is  merely  adapted  for  the  imago,  and  the 
original  design  is  constant,  even  in  the  structures  of 
the  most  highly  elaborated  insects.  In  its  simple 
form,  in  a  vermiform  *  larva,  the  system  exists  in  the 


24  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

form  of  two  longitudinal  cords,  extended  from  the 
tail  end  of  the  body  along  the  median  line  of  the 
under-surface,  parallel  with  each  other  and  close 
together,  excepting  at  their  anterior  part,  where  they 
separate  and  pass  upwards  to  encircle  the  gullet  be- 
tween them,  re-uniting  above  it  in  the  head.  Each  of 
the  cords  possesses  a  series  of  enlargements,  or 
ganglia,  throughout  its  course,  situated  at  certain 
distances  apart,  their  number  corresponding  to  the 
number  of  the  larval  segments.  They  are  precisely 
similar  in  position  in  both  cords.  Though  appar- 
ently a  simple  structure,  each  cord  is  in  reality 
composed  of  two  distinct  but  closely  united  columns 
of  fibres,  placed  one  upon  the  other.  The  under  or 
external  column,  which  is  nearest  to  the  exterior  of 
the  body,  alone  bears  the  ganglia,  the  upper  one, 
next  to  the  digestive  organs,  is  entirely  wanting  in 
knots.  These  cords  together  are  believed  to  repre- 
sent the  cerebro-spinal  system  of  vertebrates.  The 
ganglion-less  internal  column  of  either  cord  is  prob- 
ably analogous  to  the  motor  nerves  of  the  higher 
animals,  and  the  external  column  which  is  possessed 
of  ganglions,*  answers  to  the  sensitive  nerves  of  the 
vertebrata.  Thus  the  two  cords  are  each  composed 
of  a  motor  and  a  sensitive  column.  The  double 
ganglia  in  the  head,  situated  over  the  gullet,  are 
the  largest,  and  represent  the  brain.  These  and  the 
ganglia  previously  described  regulate  the  animal  life 
of  the  insect.  The  vegetative  life  beyond  will-control 
is  maintained  by  an  off-shoot  from  the  principal 
nervous  structures. 

Just  as  the  body  segments  of  the  larva  coalesce  in 


I  METAMORPHOSES  OF  INSECTS  25 

the  perfect  insect,  so  also  portions  of  the  nervous 
structures,  the  disposition  of  which  is  in  remarkable 
relation  to  the  segments,  become  concentrated  to 
perform  the  perfected  functions  of  this  wondrous 
system.  Instead  of  the  nervous  matter  being  almost 
equally  distributed  to  every  segment,  the  ganglia 
of  the  different  segments  approach  and  become 
aggregated,  the  cords  are  shortened  and  enlarge  into 
fresh  trunks,  and  nerves  alter  in  position  and  unite 
into  one  bundle,  changes  that  are  brought  about  and 
rendered  necessary  by  the  other  changes  that  take 
place  in  the  body.  This  concentration  is  most 
marked  in  insects  that  undergo  complete  metamor- 
phoses. The  greater  proportion  of  the  nervous 
masses  is  removed  to  the  head  and  thorax,  appar- 
ently as  a  means  of  concentrating  the  energies  of 
these  particular  regions.  In  some  insects  especially, 
the  ganglia  are  usually  aggregated  together  in  certain 
segments,  in  the  part  of  the  body  that  is  very  actively 
employed.  A  most  curious  union  and  complexity 
occurs  in  the  distribution  of  nerves  to  the  wings. 
These,  the  most  powerful  and  constantly  employed 
organs,  must  act  not  only  with  energy,  but  in  per- 
fect unison  with  each  other,  and  hence  must  be 
supplied  with  power  from  the  same  centre.  The 
union  exists  in  many  insects  of  rapid  or  long- 
continued  flight,  while  in  heavy  fliers,  or  those 
accustomed  to  exert  themselves  for  but  short  dis- 
tances, such  combination  is  absent.  The  ganglia 
which  form  the  brain  are  small  in  the  larva  in 
relation  to  the  size  of  the  head.  They  increase  in 
the  pupa,  and  attain  their  full  development  near  the 


26  ROMANCE  OF  THE   INSECT  WORLD      CHAP. 

termination  of  that  state.  Then  the  cerebral  mass 
acquires  a  compact  form,  it  is  more  uniformly  opaque 
than  the  other  ganglia,  and  fills  up  most  of  the  cavity 
that  incloses  it. 

If  the  metamorphoses  of  the  nervous  structures  are 
wonderful,  calling  fresh  senses  and  faculties  into  play, 
how  shall  be  characterised  the  changes  that  take 
place  in  the  organs  of  respiration  ?  There  can  be  no 
comparison  between  the  feeble  respiratory  *  efforts  of 
a  sluggish  caterpillar  or  grub,  and  the  amount  of 
breathing  energy  of  a  vigorous  and  nimble  insect. 
The  mode  whereby  an  insect  breathes  is  very  dif- 
ferent from  ours.  It  does  not  draw  in  air  through 
one  mouth,  neither  has  it  lungs,  nor  is  the  fluid 
answering  to  blood,  which  the  air  has  to  purify, 
contained  in  veins,  it  bathes  the  internal  system. 

When  the  interior  of  an  insect  is  carefully  investi- 
gated, a  multitude  of  the  tiniest  and  most  delicate 
tubes  are  seen  branching  to  right  and  left,  on  one  side 
towards  the  skin  ;  on  the  other  they  are  distributed 
to  the  middle  of  the  body,  they  cover  the  digestive 
organs,  and  enter  amongst  the  tissues.*  These  are 
air-tubes,  known  as  tracheae,  their  duty  being  to 
convey  the  air  through  every  part  of  the  insect.  A 
trachea  is  a  tube  formed  of  two  layers  of  membrane, 
inclosing  between  them  a  spiral  convoluted  thread. 
It  is  kept  open  by  means  of  the  spiral,  which  is  very 
compressible,  so  that  the  amount  of  air  any  trachea 
may  contain  varies  according  to  circumstances.  The 
outside  air  gains  admission  to  the  tubes  through 
small  apertures,  or  mouths,  called  spiracles,  which 
are  situated  generally  at  regular  distances,  their 


i  METAMORPHOSES  OF  INSECTS  27 

number  being  usually  nine  on  each  side  of  the  insect— 
a  pair  for  the  first  segment  of  the  thorax,  and  one  for 
each  of  the  eight  anterior  segments  of  the  abdomen. 
Sometimes,  as  in  the  case  of  fly-maggots,  there  is 
only  a  pair  of  spiracles,  which  are  placed  at  the  end 
of  the  body  or  near  it.  These  larvae  embed  them- 
selves in  their  nutriment,  and  would  be  stifled  were 
they  unable  to  draw  in  air  through  the  exposed  tip  of 
the  tail.  Spiracles  are  of  many  forms  of  structure. 
Suffice  it  to  say,  they  admirably  guard  the  entrances 
to  the  tracheae,  and  are  capable  of  closing  them, 
preventing  the  intrusion  of  foul  air  and  other  im- 
purities ;  this  also  permits  of  the  retention  of  large 
quantities  of  air  in  the  tubes.  The  spiracles  of  the 
abdomen  are  always  much  smaller  than  those  of  the 
thorax,  and  the  posterior  *  ones,  which  were  very  im- 
portant in  the  larva,  are  almost  imperforate  in  the 
later  time  of  growth.  The  circumstance  arises,  prob- 
ably, from  the  change  that  takes  place  as  regards 
the  region  of  the  body  in  which  respiration  is  prin- 
cipally carried  on  in  the  two  stages  of  insects.  In 
the  larva  it  takes  place  chiefly  in  the  abdomen,  in  the 
imago  in  the  thorax.  In  larvae  the  tracheae  are  always 
more  diminutive  than  in  perfect  insects  compared 
with  the  size  of  the  individual,  and  are  smallest  in 
the  footless  larvae  of  the  bee  family,  which  live  long 
in  closed  cells. 

Some  larvae  and  pupae  that  inhabit  the  water 
breathe  like  fishes  by  means  of  branchiae,  or  gills, 
respiring  the  air  which  is  mechanically  mixed  with 
the  water.  These  branchiae  are  simply  expansions 
of  the  external  surface  of  the  body,  and,  as  a  rule, 


28  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

are  extended  outwards  from  the  sides.  The  insect 
possesses  the  voluntary  power  of  moving  them  at 
pleasure,  and  thus  effects  constant  renewal  of  the 
water  in  contact  with  the  organ.  They  are  abun- 
dantly supplied  with  minute  ramifications  *  of  the 
tracheal  vessels,  which  are  believed  to  convey  the  air 
that  the  branchiae  absorb  into  the  main  tubes,  to  be 
distributed  over  the  whole  interior  of  the  body,  as  in 
insects  that  live  in  the  open  atmosphere.  Branchiae 
are  of  various  kinds,  but  the  most  common  one 
consists  of  slender  hair-like  structures,  growing 
together  in  tufts,  as  in  the  young  of  the  gnat. 

All  perfect  insects,  whether  they  are  inhabitants  of 
the  air  or  water,  breathe  air  alone.  By  the  time  that 
this  stage  is  reached,  the  branchiae,  or  other  curious 
adaptations  for  the  larvae,  where  they  were  present, 
are  no  longer  distinguishable,  and  spiracles  are 
always  developed  at  a  part  of  the  body  at  which  the 
branchiae  were  attached.  After  metamorphoses,  the 
water-beetle  (Dytiscus),  for  example,  which  leads  an 
amphibious  life,  has  the  ordinary  spiracles  for  res- 
piratory purposes ;  but  they  are  situated  on  the 
back,  enabling  the  insect  to  breathe  readily  by 
coming  to  the  surface. 

In  the  larvae  of  aH  insects,  the  internal  respiratory 
organs,  or  tracheae,  are  simply  elongated  and  ramified 
tubes.  But  in  adults  these  tubes  suffer  certain  modi- 
fications, becoming  dilated  into  an  immense  number  of 
minute  vesicles,  or  sacs,*  a  development  well  adapted 
to  meet  the  exigencies  of  increased  force  and  activity 
of  habit.  It  not  only  allows  of  most  extensive  respi- 
ration, it  enables  the  insect  to  alter  its  specific 


I  METAMORPHOSES  OF  INSECTS  29 

gravity  by  enlarging  its  bulk,  rendering  it  better  able 
to  support  itself  on  the  wing  with  little  muscular 
effort.  That  this  is  the  use  of  the  sacs  may  be 
inferred  from  their  entire  absence  in  larvae,  and  in 
insects  that  are  not  addicted  to  forsake  the  ground  ; 
while  they  are  largest  and  most  numerous  in  volants 
having  the  longest  and  most  powerful  flight.  It 
would  be  impossible  to  exaggerate  the  advantage  of 
this  beautiful  provision  to  the  humble-bee,  which  is 
compelled  to  be  constantly  on  the  wing.  Its  large 
and  cumbrous  body  is  fitted  for  all  purposes  of 
strength,  but  would  undoubtedly  occasion  it  inconve- 
nience and  fatigue,  were  the  apparently  unwieldy 
structures  not  lightened  in  this  remarkable  manner. 
The  development  of  the  vesicles  begins  at  about 
the  period  when  the  larva  ceases  to  feed,  preparatory 
to  change  to  pupa.  When  an  insect  is  quiet,  or 
is  walking,  it  breathes  slowly,  and  there  is  little 
air  in  the  tracheae.  The  body  is  heavy,  and  must 
contain  more  air  before  the  creature  can  fly.  Its 
act  of  respiration  at  this  moment  resembles  that  of 
birds  under  the  same  circumstances.  It  elevates 
its  elytra,  the  anterior*  pairs  of  spiracles  are  opened, 
and  the  air  rushing  into  them,  is  extended  over 
all  the  vesicles.  The  air-bags  expand,  which  in- 
creases the  bulk  of  the  body,  rendering  it  light  in 
relation  to  the  bulk  of  air  it  replaces,  so  that  when 
the  spiracles  are  closed  at  the  instant  the  insect 
makes  the  first  stroke  with  its  wings,  it  is  able  to 
rise,  and  endure  sustained  and  forcible  flight  with- 
out excess  of  exertion.  Explanation  is  here  obtained 
of  the  long  and  elevated  voyages  undertaken  by 
hordes  of  locusts,  which  are  not  conspicuous  for 


30  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

their  lightness  or  over-activity.  The  muscular  efforts 
of  prolonged  flight  also  heighten  the  animal  tem- 
perature, and  this  tends  to  rarefy  the  air  contained 
in  the  vesicles  and  tracheae. 

The  question  still  naturally  presents  itself:  Why 
do  insects  undergo  metamorphoses  ?  Why  should 
they,  in  attaining  to  maturity,  pass  through  such 
remarkable  development  ?  and  Why  should  the 
course  of  development  be  apparently  separated  into 
three  or  four  distinct  states,  by  marked  alteration  in 
form  ? 

In  the  first  place  it  must  be  observed  that  most 
of  the  animal  creation,  of  the  higher  classes  at  any 
rate,  have  equally  to  submit  to  metamorphoses,  or 
in  other  words  to  difference  in  shape  and  appear- 
ance, and  also  in  structure  of  internal  organs,  in 
their  early  life  and  in  maturity.  Thus  many  animals 
which  when  mature  differ  widely,  show  points  of 
resemblance  to  one  another  in  their  young  state. 
Besides,  the  embryo  of  every  organism  is  believed 
to  portray,  more  or  less  completely,  the  form  and 
structure  of  its  less  modified  progenitors,  so  that  the 
changes  of  a  single  individual  as  it  were  exhibit  in 
miniature,  and  in  short  space  of  time,  organic  evo- 
lution in  general,  which  ages  of  indefinite  duration 
have  been  requisite  to  bring  about.  In  fact  the 
great  majority  of  animals  do  undergo  well-marked 
metamorphoses,  but  often  those  most  pronounced 
are  passed  through  within  the  egg,  previous  to  birth, 
and  thus  are  not  revealed,  except  to  the  eyes  of 
the  curious.1 

Birth,  it  must  be  remembered,  is  not  the  beginning 
1  Sir  John  Lubbock.  Herbert  Spencer. 


METAMORPHOSES  OF  INSECTS  31 

of  life,  but  merely  a  particular  stage  in  the  process  of 
development.  The  condition  of  the  young  may  be 
well  advanced  before  this  event,  or  the  reverse,  birth 
may  occur  at  an  early  period  of  development,  and 
causes  for  the  difference  are  readily  discovered.  Thus 
the  apparent  total  discrepancy  between  the  meta- 
morphoses of  insects  such  as  the  locust  or  grasshopper, 
and  the  bee  or  fly.  The  two  insects  first  mentioned 
have  become  highly  developed  before  birth,  the  bee  and 
fly  have  emerged  into  the  world  from  the  egg  ere 
metamorphoses  have  far  progressed.  The  terms  larva 
stage  and  pupa  stage  are  therefore  somewhat  arbitrary, 
since  larvae  at  their  birth  from  the  egg  are  in  many 
stages  of  youthful  development. 

The  metamorphoses  of  insects  depend  then  first  on 
the  fact  that  the  young  quit  the  egg  at  a  more  or  less 
immature  stage  of  development.  The  external  forces 
act  upon  them  in  their  preparatory  state,  and  are 
different  from  those  which  affect  the  mature  form. 
Consequently  it  need  cause  us  no  surprise  to  find  that 
larvae  and  pupae  undergo  changes  which  have  refer- 
ence to  their  immediate  wants,  rather  than  to  the 
condition  which  they  will  ultimately  assume. 

As  to  the  second  part  of  our  subject :  the  ap- 
parent separation  of  the  development  of  insects  into 
distinct  stages.  There  is  this  remarkable  point  to 
be  observed,  that  whereas  the  alterations  in  many 
animals  go  on  so  ceaselessly  and  so  slowly  that  we  fail 
to  perceive  them,  in  insects  the  changes  appear  to  be 
excessively  sudden.  This  does  not  apply  to  Orthoptera 
and  others  which  undergo  incomplete  metamorphoses, 
whose  development  from  birth  to  mature  life  is  gradual 


32  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

and  not  violent  and  great.  But  leaving  these  cases 
out  of  the  question,  the  fact  remains  that  an  insect's 
life  is  generally  apparently  devisable  into  four  well- 
marked  states,  and  the  change  from  the  one  to 
the  other  appears  to  be  quite  abrupt.  In  reality  the 
metamorphoses  of  insects,  like  those  of  all  other 
animals,  arc  continuous.  The  whole  alteration,  from 
the  egg  to  the  caterpillar,  to  the  pupa,  and  from  this 
to  the  perfect  insect,  proceeds  gradually,  and  the 
striking  changes  in  outward  form,  which  take  place 
from  time  to  time  and  very  rapidly,  are  simply  due  to 
a  throwing  off  of  the  outer  skin — revealing  a  creature 
which,  far  from  being  new,  has  been  in  preparation 
for  days  ;  sometimes  for  months.1 

The  skin  of  an  insect  is  very  different  from  our  own 
and  from  that  of  other  vertebrate  animals.  It  serves 
in  place  of  a  bony  skeleton,  and  is  more  or  less  hard 
because  to  it  the  muscles  are  attached.  When  it  is 
once  made  it  cannot  be  altered,  and  consequently 
no  change  of  form  is  possible  without  a  cast  of 
skin.  In  the  case  of  many  larvae  the  moultings 
are  necessitated  principally  by  growth  and  increase  in 
size ;  the  alterations  of  structure  are  confined  to  the 
two  last  and  more  important  skin-sheddings.  Thus, 
then,  the  apparent  abruptness  of  the  changes  of 
insects  is  to  be  attributed,  in  great  measure,  to  the 
peculiar  nature  of  their  skin. 

That    material  change   of  form    is    often   delayed 

until   towards   the    latter    end    of    development,   or 

until    the    period    of  pupa,    may   be    accounted    for 

partly  by  the  structure  of  the  mouth.     That  of  the 

1  Sir  John  Lubbock. 


I  METAMORPHOSES  OF  INSECTS  33 

caterpillar  is  provided  with  jaws,  fitted  for  eating 
leaves,  whereas  the  mouth  of  the  butterfly  is  suctorial, 
and  capable  only  of  sucking  the  nectar  from  flowers. 
It  is  clear  that  were  the  mouth  of  the  larva  meta- 
morphosed into  that  of  the  perfect  insect  by  a  series 
of  small  changes,  the  insect  in  the  meanwhile  would 
be  unable  to  feed,  and  must  die  of  starvation  in  the 
midst  of  plenty.  In  insects  like  the  locust,  whose 
changes  are  gradual,  the  mouth  of  the  so-called  larva 
resembles  that  of  the  perfect  form. 

No  doubt  to  this  change  in  the  mouth-parts,  and  to 
the  similarly  rapid  and  extensive  alterations  going 
on  in  the  pupa,  is  to  be  attributed  the  strange,  and 
otherwise  incomprehensible,  immobility  of  this  re- 
markable period.  Not  only,  as  in  that  of  a  butter- 
fly, the  mouth  is  in  a  state  of  transition,  the  digestive 
organs  and  the  important  muscles,  and  even  the 
nervous  system,  are  in  course  of  rapid  change.  It 
must  not  be  forgotten  that  all  insects  are  inactive  for 
a  longer  or  shorter  time  after  each  moult.  The  period 
of  inaction  varies,  being  short  as  a  rule  when  the 
change  is  slight,  and  becomes  correspondingly  pro- 
longed as  the  change  increases  in  magnitude.  The 
quiescence  of  the  pupa  is  therefore  not  a  condition 
peculiar  to  this  stage,  but  an  exaggeration  of  the  rest 
that  has  succeeded  every  previous  change  of  skin.1 

1  Sir  John  Lubbock. 


D 


CHAPTER    II 

FOOD      OF     INSECTS 

Chief  sources  of  food — Almost  limitless  choice  from  vegetable 
world — Death's  Head  Moth  as  a  thief— Animal-feeders — 
Parasitic  Hymenoptera  and  others — Mighty  business  of 
insect-parasites  upon  insects— Larva  of  the  Tabby— An- 
other strange  food  of  animal  derivation — Ants  and  their 
aphides — Intimate  connection  of  ants  with  other  insects 
—Usual  restriction  of  insects  to  vegetable  or  animal  diet- 
Change  of  diet  at  different  stages  of  life — Need  of  nurses 
by  the  young  of  the  Social  Hymenoptera— Livelihood  with- 
out industry  —  Slave-makers — Honey-ant — Analogy  be- 
tween its  economy  and  that  of  bee  in  storage  of  food — 
Harvesting  ants  in  the  East,  in  Europe,  in  America— Time 
of  feeding— Instruments  of  nutrition— High  adaptation  of 
Lepidoptera  to  floral  diet — Means  of  procuring  food — 
Stratagem  of  ant-lion. 

LIKE  the  rest  of  living  creatures,  insects  derive  their 
nourishment  chiefly  from  the  animal  and  vegetable 
kingdoms,  but  they  enjoy  peculiar  advantage  over 
others,  in  that  while  the  larger  animals  are  more  or  less 
restricted  in  choice,  as  regards  the  vegetable  kingdom 
especially,  the  bill  of  fare  presented  by  nature  to  our 
little  subjects  is  practically  almost  without  limit. 
From  the  mighty  banyan  tree  of  India,  covering  acres 


CHAP.  II  FOOD  OF  INSECTS  35 

with  its  stems  and  foliage,  down  to  the  tiny  fungus 
scarcely  visible  to  the  naked  eye,  perhaps  not  a  single 
plant  exists  which  does  not  furnish  forth  delicious 
eating  to  some  one  of  the  vast  tribes  of  insects.  How 
different  it  is  with  the  more  imposing  beings  !  To 
them  a  considerable  amount  of  vegetation  is  abso- 
lutely poisonous — the  acrid  euphorbias,  the  henbane, 
hemlock,  and  deadly  nightshade,  and  a  still  greater 
proportion,  if  it  is  not  actually  injurious,  is  so  dis- 
tasteful as  to  be  seldom  or  never  utilised.  The 
common  nettle  is  by  no  means  highly  esteemed 
by  ourselves  or  by  the  higher  animals  in  general, 
yet  it  is  all-important  to  insects,  since  it  sustains 
the  life,  so  at  least  it  has  been  computed,  of  no 
fewer  than  thirty  distinct  species  ;  and  the  cabbage, 
while  it  is  serviceable  enough  in  its  way  to  man,  is  of 
inestimable  value  to  insects,  which  to  the  number  of 
two  hundred  kinds  feed  upon  its  substance,  or  upon 
insect  vegetarians  that  indulge  in  this  diet. 

The  larger  herbivorous  animals  have  to  remain  con- 
tent with  certain  parts  of  plants.  They  can  subsist 
upon  the  leaves,  the  seeds,  the  fruits,  occasionally  on 
the  tender  stems  and  roots ;  the  flowers  are  attacked 
rarely,  the  woody  trunks  of  trees  never;  but  to  insects 
no  portion  could  be  named  that  ever  comes  amiss. 
Not  that  insects  are  indiscriminate  feeders,  generally 
speaking ;  far  from  it.  Many  are  restricted  to  one 
particular  sort  of  plant,  and  having  fed  for  a  time  on 
it,  will  die  rather  than  partake  of  change,  and  their 
size  is  such  that  they  can  select  a  special  portion  with 
the  utmost  nicety.  Among  those  that  appreciate  the 
roots  and  stems,  some  confine  themselves  solely  to  the 

D  2 


36  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

outer  bark  ;  the  elm-tree  beetle  (Scolytus)  burrows 
mainly  in  the  inner  and  softer  layers,  the  goat-moth 
caterpillar  penetrates  to  the  living  wood,  and  others, 
as  the  beetle  that  infests  the  pine,  bore  into  the  central 
pith  of  young  shoots,  doing  incalculable  injury  to 
pine  plantations.  To  turn  to  those  whose  preference 
is  for  leaves  and  leaf-blades,  the  plant-lice,  or  aphides 
as  they  are  called,  imbibe  alone  the  juice  or  sap ;  a 
large  number  of  the  young  of  tiny  beetles,  flies,  and 
moths  taste  solely  the  cellular  substance,  or  par- 
enchyma,* disdaining  the  tough  skin  or  cuticle  as 
being  much  too  gross  for  their  delicate  appetites ;  at 
times  only  the  lower  surface  of  leaves  is  eaten ;  while 
caterpillars  as  a  rule  are  far  from  dainty,  and  de- 
molish leaves  whole  and  entire.  With  respect  to 
insects  addicted  to  flowers,  the  earwigs  and  thrips, 
for  example,  choose  the  beautiful  coloured  petals  ; 
some  select  the  pollen;  and  an  innumerable  host — 
moths  and  butterflies,  bees,  ants,  flies,  and  many 
more — make  any  effort  to  obtain  the  honey,  that 
especial  delicacy  secreted  in  the  nectaries.  The 
Death's  Head  Moth  is  excessively  fond  of  it,  and  enters 
the  hives  of  bees,  knowing  in  some  astonishing  way 
that  honey  is  to  be  had  there.  Oddly  enough,  the  bees 
do  not  rush  upon  the  intruder  and  thief,  but  use  every 
artifice  in  their  power  to  exclude  it,  or  to  wall  it  up. 

Nor  are  insects  restricted  to  vegetables  in  their  fresh 
or  unmanufactured  state.  They  will  secure  their 
livelihood  from  a  piece  of  furniture,  or  from  the  wood- 
work of  buildings  hundreds  of  years  of  age  ;  they 
even  feast  upon  what  one  would  imagine  had  surely 
been  robbed  of  all  sweetness  and  succulence — the 


n  FOOD  OF  INSECTS  37 

dried  flowers  of  a  botanist's  collection.  Nevertheless 
their  bodies  are  often  as  well  stocked  with  fluids  as 
are  leaf-fed  caterpillars. 

Insects  that  feed  on  animals  can  boast  of  a 
diversity  of  food  nearly  equally  great.  While  the 
Sexton,  or  burying  beetles  favour  dead  carcases,  the 
majority  are  adapted  for  living  prey.  A  class  of 
these,  the  parasites,*  form  one  of  the  most  curious 
and  interesting  phases  of  all  methods  of  insect  life. 
There  are  the  Strepsiptera,  parasitic  throughout 
their  lifetime  upon  bees  and  wasps.  There  are 
the  gad-flies,  which,  as  adults,  pierce  the  skin  of 
cattle  and  horses,  maybe  of  ourselves,  and  suck 
the  blood.  There  are  the  young  of  various  bot- 
flies that  insinuate  themselves  beneath  the  hide  of 
the  ox,  or  deer,  or  goat,  and  procure  regalement 
in  the  swelling  caused  by  the  irritation  produced. 
They  likewise  penetrate  into  the  nostrils  and  head  of 
sheep,  and  the  stomach  of  the  horse  or  cattle,  being 
carried  thither  by  the  tongue  of  the  animal  in  licking- 
its  coat,  whereon  the  insect  mother  had  previously  laid 
her  eggs.  The  mites,  and  ticks,  and  fleas  infesting 
animals  and  birds  need  not  be  more  than  mentioned. 
Numerous  flesh-feeders  kill  their  prey  outright.  They 
devour  either  its  solid  parts,  or  merely  drink  in  its 
juices,  rejecting  the  dry  frame. 

The  subject  of  insect  parasitism  upon  insects  is  a 
very  fascinating  one,  but  for  want  of  space  it  is  im- 
possible to  linger  long  upon  it  here.  Unfortunately, 
anything  like  an  adequate  conception  of  the  absorbing 
interest  of  the  study  cannot  be  gained  by  a  brief 
notice.  The  leading  parasitic  families  of  the  order 


38  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

inclusive  of  the  bees  (Hymenoptera)  constitute  a 
little  world  by  themselves,  but  though  their  numbers 
are  enormous,  all  alike  are  guided  by  the  same  general 
habits  and  instincts.  Few  insects,  if  any,  are  exempt 
from  their  attacks.  Usually  the  female  seeks  out  a 
caterpillar,  a  larva,  or  insect  suited  to  her  purpose, 
and  lays  her  eggs  in  or  on  its  body,  and  the  larvae 
that  are  born  of  these  eggs  feed  upon  the  fatty  tissues 
of  their  host,  leaving  its  vital  organs  for  a  time  unin- 
jured, for  were  the  host  to  die  the  parasites  could  not 
survive.  The  internal  parts  of  the  victim  are  not  de- 
voured until  the  parasitic  larvae  are  nearly  full-grown 
and  fed,  and  ready  to  change  into  pupae,  when  a  pro- 
longation of  the  life  of  the  unfortunate  creature  is  un- 
necessary. In  some  cases  the  victim,  should  it  be  a 
caterpillar,  continues  to  feed  and  live  as  though  nothing 
were  amiss  subsequent  to  its  reception  of  its  unwel- 
come guests.  It  may  even  manage  to  turn  to  chrysalis; 
but  it  never  attains  to  the  perfect  form,  when  it  could 
lay  eggs  and  reproduce  its  kind,  because  invariably  ere 
it  reaches  the  final  stage  the  maturing  larvae  it  con- 
tains have  destroyed  it,  by  a  slow  but  sure  consump- 
tion. Thus  it  often  happens  to  a  butterfly  collector 
who  has  been  looking  forward  to  see  a  fine  butterfly 
emerge  from  its  chrysalis,  to  be  disappointed,  and  to 
feel  chagrin,  by  the  appearance  of  several  little  parasitic 
Hymenoptera,*  which,  unknown  to  him,  the  butterfly 
has  all  along  been  sustaining,  and  to  whom  it  has  at 
last  been  compelled  to  yield  up  its  life. 

When  a  parasite  in  open  day  finds  an  insect  that 
will  answer  admirably  as  the  nourishment  for  her 
future  larvae,  and  deposits  an  egg  in  it,  the  act  does 


II  FOOD  OF  INSECTS  39 

not  involve  any  marked  degree  of  cleverness,  nor  is  it 
difficult  to  comprehend.  But  by  what  power  does  she 
become  aware  of  the  presence  of  a  suitable  host  inside 
fruit  or  the  branch  of  a  tree,  and  completely  concealed 
from  sight  ?  She  discovers  the  exact  spot  where  it 
lies  hid,  and,  with  her  long  ovipositor,*  pierces 
through  the  bark,  or  solid  wood,  or  skin,  as  the  occa- 
sion requires,  driving  her  eggs  into  closest  contact  with 
the  selected  victim.  When  one  ability  fails  to  be  use- 
ful under  the  circumstances  of  life,  another  is  believed 
to  come  into  prominence  to  supply  its  place.  Her 
eyes  *  cannot  assist  her  to  this  knowledge,  which  has 
been  attributed  to  the  sense  of  smell,  aided  perhaps 
by  that  of  hearing,  but  these  matters  await  elucidation. 
The  mother's  capacity,  as  it  were,  to  gauge  the  appe- 
tites of  her  young  is  equally  extraordinary — creatures 
of  which  she  can  know  nothing.  She  is  no  miserly 
caterer,  but  is  ever  careful  to  provide  them  with  nourish- 
ment in  quantity  enough  and  to  spare.  A  large  parasite 
lays  only  a  single  egg  at  a  time,  because  its  larva  is 
capable  of  consuming  the  recipient's  entire  substance  ; 
had  it  been  accompanied  by  brother-larvae,  they  must 
all  have  come  to  grief  by  starvation.  If  a  somewhat 
smaller  parasite  avails  itself  of  a  great  host,  then  two  or 
three  eggs  are  introduced ;  and  should  the  ichneumon  * 
be  very  diminutive,  the  host  may  receive  as  many  as 
fifty  or  sixty,  or  more.  But  these  insects  seem  in- 
capable of  altering  their  proceedings  according  to  the 
occurrence  of  events.  Each  follows  the  same  plan  for 
generation  after  generation,  without  variation.  If  a 
large  parasite  came  across  a  bigger  host  than  it  had 
ever  met  before,  it  would  bestow  only  a  single  egg 


40  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

upon  it,  and  a  small  parasite  would  always  lay  pro- 
lifically,  whatever  might  be  the  size  of  the  receiver 
detected. 

Sometimes  parasitic  larvae  are  so  excessively  minute 
as  to  find  accommodation  and  nourishment  in  the 
eggs  of  insects.  Those  of  many  Lepidoptera,  of 
a  small  beetle  and  of  the  dragon-fly  are  thus  de- 
stroyed. Pupae  are  also  invaded,  as  well  as  imagos. 
Of  all  the  conditions,  however,  that  of  the  grub  or 
larva  is  princially  liable  to  these  terrible  attentions, 
because  it  is  often  the  one  of  longest  duration,  and 
therefore  best  calculated  to  carry  out  the  object  of  the 
parasite  ;  whereas  the  adult,  and  chrysalis,  and  egg- 
stages  are  in  many  instances  brief,  and  more  likely, 
the  first  and  last  especially,  to  be  cut  short  by  acci- 
dent. Strange  to  say,  insects  which  have  long  adult 
life  are  subject  to  parasites,  whilst  those  to  whom  an 
ephemeral  career  is  meted  out  go  free.  Weevils  are 
long-lived,  and  though  encased  in  what  would  seem 
impenetrable  armour,  and  able  to  withstand  the 
assaults  of  many  a  large  and  open  foe,  they  are  per- 
vious to  the  lancet-like  sting  of  the  indefatigable  and 
more  insidious  assailants. 

These  parasites  have  a  mighty  business  in  the  world, 
being  the  means  employed  by  nature  to  keep  within  due 
bounds  the  superabundant  multiplication  of  the  phy- 
tophagous, or  vegetable-feeding,  insects,  which  would 
often  increase  to  an  unwarrantable  extent,  and  do  in- 
finite mischief  were  it  not  for  these  appointed  checks. 
They  perform  a  marvellous  work  to  our  advantage, 
which  is  the  more  evident  when  we  consider  them  in 
relation  to  insects  injurious  to  the  crops.  They  afford 


ii  FOOD  OF  INSECTS  41 

a  wonderfully  great  protection  from  those  most  trouble- 
some pests,  one  in  a  sense  superior  to  all  the  arti- 
ficial methods  of  prevention  that  were  ever  devised, 
inasmuch  as  they  cost  us  absolutely  no  trouble  and  no 
expense.  The  balance  of  life  between  vegetables,  in- 
sect pests,  and  their  parasites  is  indeed  extraordinary, 
and  we  cannot  be  too  careful  of  instituting  measures 
tending  to  upset,  even  ever  so  little,  nature's  ap- 
pointed ways. 

Not  only  animals  themselves,  animal  matters  in 
great  variety  constitute  the  food  of  many  insects. 
Hair,  wool,  leather,  silk,  fur,  even  feathers,  are  not  de- 
spised, and  the  grub  of  a  beetle,  with  powers  of  diges- 
tion that  a  dyspeptic  might  envy,  can  subsist  on  horn. 
The  larva  of  a  moth  popularly  styled  the  Tabby 
(Aglossa  pingiiinalis},  known  both  in  houses  and 
stables,  has  the  still  more  remarkable  fancy  for  grease 
in  any  shape  or  form — for  greasy  horse-cloths,  kitchen 
fat,  and  so  on — and  nothing  could  be  more  interesting 
and  instructive  than  the  marked  adaptation  of  its 
structures  for  the  mode  of  life  it  adopts.  Its  habit  is 
to  feed  by  diving  into  the  food-stuffs  bodily.  It  is  in 
no  danger  of  being  suffocated,  for  its  breathing  ap- 
paratus is  arranged  to  prevent  the  fat  from  clogging 
its  pores.  Kitchen  fat  and  horse-cloths  are  products 
of  a  more  or  less  recent  civilisation,  and  probably  no 
one  will  deny  that  these  larvae  have  acquired  their 
peculiarities,  enabling  them  to  obtain  food  under  such 
extraordinary  conditions,  at  a  period  subsequent  to 
the  introduction  of  the  fatty  materials  in  question 
In  a  word  the  moths  are  a  new  species,  evolved  from 
ancestors  which  led  different  lives.  To  reject  this 


42  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

opinion  is  to  believe  in  their  special  creation  for  the 
purpose  of  relieving  the  world  of  a  little  superfluous 
fat.  Another  set  of  caterpillars  (Galleridce)  have  a 
strange  liking  for  wax,  and  to  gain  this  substance 
force  their  way  into  beehives  and  the  homes  of  wild 
bees,  protecting  themselves  from  the  revenge  of  the 
lawful  owners  of  the  nests  by  spinning  silken  web 
around  them  in  the  cells  of  the  combs — robbers 
comparable  with  the  Death's  Head  Moth. 

Ants  indulge  in  a  far  stranger  food  of  animal 
derivation — a  sweet  liquid  produced  -by  insects— 
and  often  abstract  it  direct,  warm  so  to  speak, 
from  the  living  body.  The  suppliers  are  aphides, 
or,  according  to  their  popular  appellation,  the 
plant  lice  or  green  fly,  unhappily  too  well  known 
in  every  flower  and  kitchen  garden.  On  roses,  ger- 
aniums, beans,  cabbage,  and  fruit  trees  they  multiply 
amazingly,  and  suck  away  the  richest  of  the  vegetable 
juices  by  means  of  a  rostrum  or  tube,  sometimes  of 
great  length,  with  which  they  are  provided.  Careful 
examination  of  a  plant  crowded  with  aphides  seldom 
fails  to  reveal  the  presence  of  an  ant,  and  it  is  not  by 
chance  that  this  member  of  the  "  little  people"  has 
wandered  into  the  midst  of  the  alien  assembly.  It 
has  come  with  deliberate  intention,  to  feast  off  a 
dainty  and  luscious  .meal,  a  sugary,  limpid,  viscous 
secretion  which  is  now  and  then  exuded  by  the 
aphides,  and  denominated  honey-dew.  Ants,  as 
a  rule,  do  not  wait  to  obtain  it  on  the  yielder's 
pleasure.  One  may  be  seen  to  approach  an  aphide, 
the  extremity  of  whose  body  it  rubs  gently  but 
rapidly  with  its  antennae,*  as  if  to  entice  the  insect  to 


ii  FOOD  OF  INSECTS  43 

accede  to  some  request.  The  caress  has  the  desired 
effect,  for  the  aphide  responds  to  the  call  by  eject- 
ing a  drop  of  liquid  which  the  ant  greedily  laps  up  ; 
the  aphide  in  fact  acts  as  the  ant's  cow.  No  use  of 
the  secretion  to  the  aphides  themselves  has  been 
recognised;  probably,  since  it  is  sticky,  it  is  to  their 
advantage  to  have  it  removed.  This  liquor  forms  the 
principal  nourishment  of  many  ants,  of  the  red  and 
-  yellow  kinds  in  particular,  the  different  species  of 
ants  being  chiefly  devoted  to  different  species  of 
aphis. 

Towards  the  aphides  of  their  choice  ants  extend 
special  guardianship  and  protection,  treating  them  as 
their  own  private  property,  and  resenting  on  part  of 
them  all  interference  offered  by  other  insects.  Some 
take  possession  of  a  branch  where  their  cattle 
browse,  and  hold  it  against  intruders  by  vigorously 
attacking  any  aggressor.  They  serve  as  an  efficient 
standing  army  to  the  aphides  in  return  for  the 
food  that  the  latter  furnish.  Some  ants  build  little 
walls  of  earth  over  their  aphides,  cow-sheds  they 
may  be  called,  to  prevent  them  straying.  Some 
form  a  private  covered  roadway  between  their  cattle's 
grazing  ground  and  their  nest,  placing  their  cows 
within  easy  reach  and  distance  of  communication. 
Others  of  these  ingenious  beings,  who  are  always 
busy,  have  taken  to  heart  the  lesson  of  the  necessity 
of  the  economy  of  time  and  labour.  To  save  them- 
selves repeated  and  tiresome  journeyings  to  and  fro, 
they  frequently  thoroughly  domesticate  their  cows, 
so  to  speak,  or  drive  them  in  considerable  flocks 
into  the  near  neighbourhood  of  home ;  sometimes 


44  ROMANCE  OF  THE  INSECT  WORLD      CHAP 

they  convey  them  inside  their  nest.  The  aphides 
selected  feed  on  the  sap  of  grass  and  roots,  a  nutri- 
ment that  lies  ready  to  hand  without  troubling  the 
captives  to  step  out  of  doors,  the  subterranean 
chambers  and  corridors  being  constructed  in  the 
midst  of  the  vegetation  required.  Formica  show 
themselves  good  and  attentive  masters,  and  use  their 
aphides  with  unvarying  kindness  and  consideration. 
Ants  actually  breed  their  cattle,  rearing  them 
through  the  different  stages  of  existence,  hatching 
them  out  as  though  they  were  their  own  with  the 
utmost  care  and  tenderness.  A  fact  has  been  dis- 
covered by  Sir  John  Lubbock  in  connection  with 
this  habit,  which  he  describes  as  one  of  the  most 
remarkable  he  knows  in  the  whole  history  of  animal 
life.  Certain  aphides  live  not  in  an  ants'  nest,  but 
outside  on  the  leaf-stalks  of  plants.  The  wise  and 
judicious  cattle-breeders  do  not  think  of  allowing  the 
eggs  laid  by  the  aphides  in  the  autumn  to  remain 
exposed  to  the  severity  of  the  approaching  winter 
and  innumerable  dangers.  They  collect  them  and 
bring  them  into  their  nest,  and  the  young  are  tended 
and  fed  and  kept  from  harm  by  the  ants  until  the  fol- 
lowing spring,  when  they  are  carried  again  to  the 
food-plants  on  which  they  were  at  first  deposited. 
During  all  this  period  of  watchful  superintendence 
the  aphides  are  not  of  the  slightest  use  to  their 
attendants,  who  receive  no  immediate  return  for  their 
services.  They  lavish  this  care  upon  these  insects 
with  the  expectation  of  future  payment,:  in  order  to 
have  a  fresh  stock  of  aphides  in  the  spring.  In 
this  way  they  secure  adequate  supplies  of  sweet  liquid 


ii  FOOD  OF  INSECTS  45 

food,  an  instance  of  prudence  and  foresight  unparal- 
leled in  the  annals  of  the  animal  world. 

Ants  go  similarly  in  search  of  the  cocci*  or  scale 
insects,  among  them  the  valuable  cochineal,  and 
several  Homoptera,*  such  as  Membracis  and  its  allies  ; 
they  are  also  intimately  connected  with  a  large 
variety  of  beetles.  Many  of  these,  like  the  aphides, 
live  habitually  with  the  ants  ;  at  least  between 
thirty  and  forty  different  kinds  of  beetles  arc  rarely, 
if  ever,  met  with  excepting  in  ants'  nests.  The  reasons 
for  the  retention  of  these  normal  boarders  are  un- 
known. Many  most  curious  functions  have  been 
assigned  to  them,  but  a  considerable  proportion  of  the 
co-habitants  of  the  nest  are  in  reality  ant-cows. 
Claviger  beetles  at  the  base  of  their  elytra  possess 
tufts  of  tubular  hairs  which  the  ants  take  into  their 
mouths  and  lick,  and  also  the  whole  of  the  upper 
surface  of  the  beetle's  body,  doubtless  abstracting 
some  special  secretion  that  affords  satisfaction  to  their 
palate.  In  return,  the  beetles  are  believed  to  be 
maintained  at  the  expense  of  their  grateful  hosts. 
One  quaint  little  claviger  is  blind,  and  is  apparently 
quite  a  dependent,  having  lost  the  faculty  of  feeding  ; 
at  any  rate  it  has  never  been  seen  to  take  refreshment 
alone,  this  is  invariably  administered  by  the  nursing 
ants. 

For  the  most  part,  insects  that  feed  on  vegetables 
will  not  touch  animal  matters,  and  vice  versa,  but  the 
rule  is  open  to  exception,  notably  as  regards  ants. 
Many  caterpillars,  though  plants  are  their  proper 
food,  will  occasionally  exhibit  depravity  of  taste, 
and  if  kept  with  their  own  kind,  or  with  the 


46  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

larvae  of  other  moths,  may  turn  cannibal,  and  make 
away  with  the  company.  Similarly,  the  large  green 
grasshopper  will  eat  insects  smaller  than  itself  as 
well  as  its  ordinary  vegetable  diet.  The  same  may 
be  said  of  young  caddis  flies,  and  of  the  mole 
cricket,  which  burrows  in  the  earth,  and  feasts  on 
roots.  Should  it  meet  a  worm,  or  an  insect,  on  its 
travels,  it  seems  to  see  no  reason  to  deny  itself  a 
little  variation  in  its  customary  provision  as  a  relief 
to  sameness.  On  the  other  hand,  some  carnivorous 
beetles  will  make  a  hearty  meal  off  a  putrid  fungus. 
One  small  family  of  this  order  (Dermestidse)  in  the 
larval  state  is  a  veritable  plague  in  museums,  attacking 
furs,  skins,  and  dried  flesh,  and  is  not  disinclined  to 
enjoy  bacon  and  ham.  In  the  event  of  being  unable 
to  obtain  anything  of  this  sort,  it  has  been  known 
to  pounce  upon  and  ruin  a  ship's  cargo  of  cork. 

It  is  a  very  remarkable  fact  that  insects  frequent- 
ly change  their  diet  completely  at  their  different 
stages  of  existence.  Moths  and  butterflies  in  their 
immature  condition  feed  on  leaves  and  twigs,  in 
the  interior  of  trunks  of  trees,  in  roots,  in  seeds,  or 
in  the  insides  of  fruits;  while  none  when  mature 
deigns  to  partake  of  anything  stronger  than  a  fluid, 
generally  obtained  by  a  casual  choice  and  gentle  sip 
from  the  honey-bearing  cup  of  a  lovely  flower.  In 
some  parts  of  the  world  in  the  case  of  flowers  want- 
ing in  the  secretion  of  free  honey,  these  insects  tear 
open  the  delicate  succulent  tissues  in  order  to  get  at 
the  sap;  they  rifle  the  juice  from  fruits,  such  as 
plums,  peaches,  and  oranges,  in  like  fashion.  A 
greater  change  holds  good  for  the  various  states  of 


IT  FOOD  OF  INSECTS  47 

the  Hymenoptera  or  Bee  Family.  As  imagoes  they 
are  usually  strict  vegetarians,  but  during  their  larval 
period,  while  some  live  on  plants — the  bees,  sawflies, 
and  others — many  are  absolutely  carnivorous,  and 
can  exist  only  upon  living  prey. 

It  is  customary  for  insects  to  provide  for  their  own 
wants.  A  mother  forsakes  her  young,  leaving  them  to 
get  on  as  they  best  may,  but  she  takes  care  to  deposit 
them  in  a  spot  in  the  midst  of  sustenance,  or  where 
it  may  be  readily  procured  by  the  larvae.  Some- 
times she  goes  on  foraging  expeditions,  and  stocks 
the  larder  of  her  infants  with  nourishment 
whether  of  a  vegetable  or  an 
animal  nature,  sufficient  for 
their  consumption  until  they 
reach  maturity.  Some  young, 
however,  are  incapable  of  feed-  FIG.  3.  —  A  honey-bearing 

.   ,  .  ^TM  ant  (Myrwecocystns   Mexi- 

ing     Without     assistance.          1  hey          <•«»/«)   regurgitating   honey 

-,,      _  from  her  crop  at  the  solicita- 

1'CqUire  a  Stan  Of  nurses  tO  Watch         tion  of  hungry  workers:  from 

McCook. 

over    them    day    by   day,    who 

are  industrious  and  patient  enough,  and  qualified  by 
intelligence  to  rear  their  troublesome  charges  through 
their  early  helpless  stages.  The  young  of  ants,  of  bees, 
and  wasps,  that  live  in  societies,  are  thus  dependent 
upon  their  elder  relations.  The  mouths  of  the  ants  are 
small  and  ill-developed,  possessing  two  tiny  booklets, 
perhaps  the  embryos  of  the  future  mandibles,*  but 
far  apart  from  each  other  and  of  little  use.  The 
larvae  themselves  are  too  feeble  to  move  and  seize  the 
food  were  it  placed  within  their  reach.  But  they  have 
the  instinct  to  lift  their  heads  and  gape  like  birds  new- 
hatched  to  receive  their  meals  from  their  guardian's 


48  ROMANCE  OF  THE  INSECT  WORLD     CHAP. 

jaws,  being  directed  so  to  do  by  a  tap  from  the 
latter's  antennae.  The  aliment  administered  is  be- 
lieved to  be  in  accordance  with  the  age  and  sex, 
the  females  in  all  probability  being  furnished  with 
greater  liberality,  and  with  stuff  of  a  peculiarly 
stimulating  nature.  From  the  enormous  number  of 
mouths  waiting  to  be  fed  in  a  well-filled  ants'  nest, 
day  by  day  and  several  times  a  day,  some  notion  may 
be  formed  of  the  severity  of  the  duties — and  nursing 
constitutes  merely  a  fraction  of  them — so  successfully 
undergone  by  the  unselfish  and  untiring  "  workers," 
and  we  cease  to  wonder  that  they  display  the  ac- 
tivity which  is  so  conspicuously  a  trait  of  their 
character.  Even  when  the  period  of  infancy  is  passed, 
and  the  pupa  is  extracted  from  its  silken  shroud 
and  emerges  perfect,  nourishment  is  again  given  to 
the  new-born  nursling  by  the  nurses,  who  likewise 
introduce  the  unused  inmate  to  the  common  home 
and  work.  Not  only  the  young  of  the  nest  receive 
attention.  The  foragers  on  their  return  home  gorged, 
deliver  up  a  portion  of  the  plunder  to  their  less  for- 
tunate "  grown-up "  friends,  whom  indoor  business 
has  compelled  to  remain  at  home. 

The  above  remarks  apply  almost  equally  well  to 
the  feeding  of  the  young  of  social  bees,  which  differ 
in  this  respect  from  ants,  that  they  dwell  generally 
coiled  up  within  narrow  cells.  Probably  the  bees 
who  particularly  assume  the  function  of  nurses  are 
recruited  from  the  ranks  of  the  workers  who  are 
only  recently  released  from  their  pupal  bonds. 
Possibly  the  oldest  workers  of  the  hive  are  likewise 
deputed  to  this  occupation,  in  consequence  of  their 


ii  FOOD  OF  INSECTS  49 

growing  inability  for  the  more  onerous  and  arduous 
labours  of  building  and  of  gathering  and  carrying  home 
honey.  The  larvae  of  wasps  are  somewhat  more 
hardy  than  those  of  bees,  their  head  is  larger  and  of 
greater  strength,  and  the  mouth  is  stouter.  They 
therefore  receive  occasional  bits  of  fruit  and  fragments 
of  insects  in  addition  to  the  usual  fluid,  or  very  soft 
nutriment,  upon  which  alone  ants  and  bees  are  bred. 

The  young  of  solitary  bees  and  wasps  are  able 
to  take  their  nourishment  unaided  if  it  be  placed 
beside  them.  But  the  mothers  of  certain  species 
cannot  make  such  provision,  being  deficient  in  the 
structures  necessary  to  enable  them  to  build  and 
collect  the  proper  food.  They  therefore  use  their 
wits  instead  of  labouring,  and  introduce  their  eggs 
into  a  nest  that  is  already  victualled  by  some  in- 
dustrious Hymenoptera  for  its  own  progeny.  The 
usurping  larvae  are  hatched  sooner  than  the  rightful 
inheritors  of  the  home,  and  utilise  the  nutriment 
that  surrounds  them  without  care  for  the  sorry  plight 
of  their  defrauded  companions. 

Some  kinds  of  ants  are  similarly  helpless.  Their 
difficulty  is  very  great,  for  ant-larvae  must  be  fed  from 
the  mouths  of  nurses.  The  method  of  cutting  this 
gordian  knot  of  perplexity  comprises  one  of  the  most 
curious  and  extraordinary  phases  of  the  many-sided 
ant  character ;  it  is  a  marvellous  imitation  of  the 
ways  of  man.  They  make  regular  periodic  raids 
and  forays  upon  the  nests  of  other  ants  and  carry 
off  their  workers,  training  and  subjecting  them  to 
undertake  the  offices  in  which  they  cannot  themselves 
engage.  The  adults  of  the  foreign  colonies  are  not 

E 


50  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

seized,  because  they  would  never  become  domesti- 
cated in  a  strange  home;  it  is  their  larvae  and 
pupae  that  are  taken.  When  the  captives  reach 
maturity,  they  appear  to  make  no  attempt  at  insubor- 
dination or  escape,  but  at  once  assume  the  duties  for 
which  they  were  enlisted.  These  warlike  ants  belong 
to  the  genus  Polyergus.  They  are  a  striking  instance 
of  the  degrading  effects  of  slavery,  for  they  are  not 
only  dependent  as  regards  the  care  of  their  young, 
they  have  lost  almost  every  instinct  and  power  that 
they  ever  possessed,  and,  as  a  rule,  all  building  opera- 
tions and  all  foraging  for  food  likewise  devolve  on  the 
slaves.  The  masters  will  not  even  "  do "  for  themselves, 
they  are  waited  on,  fed,  and  cleansed  by  their  willing 
serfs.  In  the  event  of  change  of  the  domicile,  the  ser- 
vants remove  their  masters  along  with  the  young  to  the 
new  abode.  But  the  Polyerges  continue  to  be  war- 
riors, and  remain  capable  of  capturing  fresh  bondsmen. 
In  other  species  of  ants  the  distinction  of  the  relative 
position  of  the  masters  and  servitors  is  considerably 
relaxed.  The  latter  are  merely  introduced  into  the 
nest  of  their  captors  to  assist  in  the  various  depart- 
ments of  labour  ;  all  alike  mingle  freely  together  and 
share  in  the  common  work  of  the  colony.  In  one 
species  of  ant,  F.  sanguined,  this  slave-making  pro- 
pensity has  been  observed  in  active  exercise  in 
England. 

Social  bees,  as  is  well  known,  lay  in  provision  in 
the  cells  of  the  comb  that  they  fashion  within 
their  nest.  It  serves  for  themselves  and  their 
young  for  a  rainy  day  and  for  winter  need.  The 
provident  habit  is  usually  denied  to  the  wasps  and 


II  FOOD  OF  INSECTS  51 

to  the  third  member  of  the  trio  of  communal  Hymen- 
optera,  the  ants,  which  are  believed  to  live  from  day 
to  day  from  hand  to  mouth.  It  would  be  almost  super- 
fluous for  ants  to  store  food,  it  is  commonly  asserted, 
since,  like  most  insects,  they  become  stupid  and 
hybernate  so  long  as  the  cold  months  last.  Whether 
this  generally  received  opinion  is  altogether  correct 
remains  to  be  seen. 

A  native  ant  of  Mexico  (Myrmecocystns  Mexicanus) 
has  recently  been  found  plentiful  in  that  section 
of  the  country  known  as  the  Garden  of  the  Gods, 
Colorado,  by  the  naturalist  Dr.  McCook.  Early  in 
life  certain  numbers  of  its  workers  begin  to  show 
unusual  distension  of  the  abdomen,  gradually  in- 
creasing as  time  goes  on,  until  this  part  of  the  body 
assumes  prodigious  proportions  in  comparison  with  the 
upper  portion,  the  head  and  the  legs.  In  perfect 
cases  it  varies  from  the  size  of  a  large  currant  to 
that  of  a  tiny  grape ;  its  appearance  resembles  a 
transparent  bubble.  The  external  covering  mem- 
brane of  this  globe  of  tissue  is  excessively  thin,  and 
one  can  see  what  is  contained  inside.  The  inflation 
is  due  to  a  great  accumulation  of  syrupy-like  liquid, 
which  is  sometimes  whitish  in  colour,  more  commonly 
of  an  amber  shade.  These  ants  are  the  living  cells 
or  storehouses  of  food  for  the  community.  A  com- 
plete analogy  may  be  established  between  the  economy 
of  this  remarkable  structure  and  habit  and  that  of 
the  bee  in  the  storage  of  honey  within  the  comb. 
The  rotund  ants  do  not  elaborate  the  secretion,  they 
are  charged  with  it  by  those  workers  which  are 
honey  gatherers,  who,  when  they  return  to  the  nest 

E  2 


52  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

after  absence  on  a  foraging  expedition,  give  up  their 
collected  supplies  to  the  distending  individuals,  who 
more  or  less  entirely  remain  at  home.     They  do  this 
by  means  of  regurgitation,  and  by  injecting  it  into 
the   mouth    of    their   wonderful    sister   formicarians. 
Within   the  latter  the  honey   is   held    in    reserve   in 
case  of  emergencies,  such  as   the  seasons  when  the 
gleanings  are  less  abundant  or  when  the  resources 
of  nature  wholly  fail.      Notwithstanding   these  dis- 
asters the  family  must  be  fed ;  and  be  it  remembered 
that   many  of  its  members — the    queen,  the   virgin 
females,  the  males,  and  the  occupants  of  the  teeming 
nurseries — all  look  to  the  workers  to  supply  them 
with  food.     Just  as  under  similar  circumstances  the 
bee  goes  to  the   honeycomb,   breaks  open  a  waxen 
cell  and  abstracts  the  contained  sweets,  so  the  worker 
ants  go  to  their  companion    honeypots    when    they 
are  hungry  or  if  desirous  of  administering  nourish- 
ment to  others.     The  bearer  from  its  store  delivers 
up  the  honey  required,  the  pensioners  lapping  it  from 
off  the  giver's  lips  as  it  gathers  there,  being  forced  up 
in   little   drops   or   globules   by  the  muscles  of  the 
abdomen.     (See  Fig.  3.) 

These  remarkable  ants  live  in  dwellings  under- 
ground, and  the  honey-bearers  may  be  seen  in 
chambers  set  apart,  in  little  rows,  clinging  by  their 
feet  to  the  ceiling,  their  sphere-like  abdomens  hanging 
downwards.  (See  Fig.  4.)  Though  it  is  a  mistake  to 
deny  these  unhappy  gorged  creatures  the  power  to 
move,  and  to  abandon  a  perch  after  it  is  adopted,  there 
can  be  no  doubt  that  movement  and  change  of  posture 
are  less  and  less  resorted  to  as  expansion  increases, 


ii  FOOD  OF  INSECTS  53 

and  when  a  well-filled  individual  loses  its  grasp  and 
falls  to  the  floor,  it  is  generally  incompetent  to 
recover  its  balance.  To  a  certain  extent  the  workers 
evidently  regard  them  as  dependents,  the  light  in 
which  they  probably  look  upon  the  other  members 
of  the  hive.  They  even  perform  their  toilet  for  them, 
though  the  rotunds  seem  able  to  assist  themselves. 

The  outer  wall  of  an  ant's  abdomen  consists  of 
a  series  of  chitinous  segmental  plates,  ten  in 
number,  five  dorsal*  and  five  ventral*  ones,  which 
overlap  one  another  like  the  tiles  of  a  roof.  These 
plates  alone  are  visible  externally  in  an  ordinary  ant. 
In  all  ants,  however,  they  are  laid  upon  (if  I  may 
so  speak)  an  inner  coat,  which  is  highly  elastic,  and 
in  ordinary  excessive  feeding  this  membrane  is 
stretched  between  the  plates,  forcing  them  apart,  the 
degree  of  separation  varying  with  the  amount  of  food 
taken.  In  the  case  of  the  honey  -  bearers  some 
of  the  plates  become  isolated,  appearing  like  little 
brown  transverse  bars  on  the  tersely-stretched  and 
lighter  coloured  wall.  Dr.  McCook  supposes  the 
honey  to  be  not  contained  within  the  stomach,  but 
in  the  crop,  an  abdominal  portion  of  the  oesopha- 
gus. The  result  is  that  the  crop  becomes  immensely 
distended,  and  almost  completely  fills  the  cavity  of 
the  abdomen,  to  the  displacement  of  the  stomach  and 
other  digestive  organs,  which  are  pushed  into  small 
space  towards  the  anal  extremity.  Sir  John  Lubbock 
mentions  another  species  of  honey-ant,  which  he 
describes  as  Camponotus  inflatus,  from  Adelaide, 
Australia.  In  it  a  similar  habit  and  modification 
have  been  evolved.  Since  the  rotunds  are  probably 


54  ROMANCE  OF  THE  INSECT  WORLD     CHAP. 

developed  from  the  ordinary  worker  and  do  not 
comprise  a  distinct  caste,  the  possibilities  of  such  en- 
largement may  exist  in  the  structure  and  functions  of 
all  honey-feeding  ants. 

The  Indians  and  Mexicans  eat  this  honey  freely, 
and  not  unusually  the  ants  are  served  at  table  as  a 
dainty  morsel,  the  head  and  thorax  being  removed. 
The  liquid  is  also  pressed  out  of  the  body,  and  forms 
the  principal  ingredient  of  an  exhilarating  drink  some- 
what like  mead.  It  is  supposed  to  possess  wonderful 
healing  properties,  and  has  a  place  among  the  native 
remedies  for  disease,  being  applied  to  bruises,  to 
swelling,  and  as  an  unguent  to  cataract  of  the  eye. 
That  it  might  ever  become  of  practical  commercial 
value  is  hopeless,  since  the  comparative  number  of 
workers  being  honey-bearers  in  a  nest  is  strangely 
small. 

The  opinion  of  many  eminent  naturalists  of  the 
present  centuries  is  opposed  to  the  belief  that  ants 
show  foresight  and  husbandry  in  the  systematic  col- 
lection and  storage  of  seed.  Ancient  books,  both 
Oriental  and  European,  show  their  writers  to  have 
been  quite  at  variance  with  the  modern  idea.  The 
authors  of  neither  period  are  altogether  in  the  right. 
It  is  a  mistake  to  deny  the  seed-storing  habit  to  any 
ants,  an  error  that  arises  from  too  hasty  generalisa- 
tion and  limited  observation.  To  attribute  it  to  ants 
in  general,  irrespective  of  species  or  country,  is 
equally  incorrect,  the  ancients  having  judged 
from  their  own  circumscribed  experience  and  the 
reports  of  others.  The  truth  is  that  the  harvesting  of 
grain  by  ants  does  occur,  but  seems  to  be  confined  to 


II  FOOD  OF  INSECTS  55 

a.  small  number  of  kinds,  and  to  tropical  and  warm 
climates.  Research  is  bringing  to  light  the  very 
interesting  fact  that  as  a  rule  in  those  countries 
where  the  ancients  lived  and  wrote,  the  harvesters 
abound  to  the  present  day.  Recent  investigators 
have  discovered  them  in  India,  and,  to  come  a  little 
nearer  home,  in  Syria  and  Palestine.  In  the  two  last 
countries  the  insects  must  have  existed  in  striking 
abundance  in  former  days,  and  have  amassed  stores 
of  grain  of  sufficient  size  to  make  them  worth  col- 
lecting. This  is  to  be  inferred  from  a  passage  in  the 
Mishna,*  being  a  quaint  bit  of  legislation  deciding  the 
property  rights  to  the  ant-stores  found  in  fields  of 
corn,  whether  they  should  appertain  to  the  gleaners  or 
the  proprietor  of  the  field  ; — the  rights  of  the  poor  little 
collectors  themselves  seem  to  have  been  beyond  the 
pale  of  consideration.  We  smile  at  the  scrupulousness 
of  a  people  who  could  legislate  upon  such  a  subject, 
one  of  those  pitiful  minima  which  even  the  Jewish 
law  might  surely  have  passed  by.  Nevertheless  the 
edict  is  an  important  one,  showing  that  these 
operations  of  the  ants  were  noticeable  enough  to  call 
for  comment. 

Nor  are  harvesting  ants  entirely  absent  from  the 
European  continent.  Two  species  (Atta  structor 
and  barbard),  being  true  harvesters,  were  discovered 
in  the  south  within  recent  years  by  the  English 
naturalist  Treherne  Moggridge.  He  watched  them 
gather  and  transport  the  seeds  of  a  large  variety 
of  plants  to  their  nests,  and  upon  excavating  the 
nests  at  different  periods  of  the  year,  he  found 
the  garnered  grain  carefully  stowed  away  for 


56  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

future  want  in  subterranean  granaries.  If  seeds 
be  placed  in  the  soil  at  not  too  great  a  depth, 
and  be  subjected  to  the  requisite  warmth  and 
moisture,  they  usually  do  one  of  two  things  after 
an  interval  of  time.  Either  they  germinate  or  they 
rot.  Those  gathered  by  these  ants  do  not  tend 
to  do  any  of  these  things.  Yet  they  lie  in  damp 
and  moist  chambers,  and  have  been  discovered 
in  genial  weather,  and  often  at  a  trifling  distance 
below  the  surface.  The  inference  is  that  the  ants 
prevent  the  grains  from  germinating,  exerting 
some  influence  which  checks  the  inherent  power 
of  nature.  It  has  been  suggested  that  the  little 
radicle,*  or  first-growing  rootlet  of  the  future 
plant,  is  gnawed  away,  which  would  effectually  put 
a  stop  to  germination.  The  idea  seems  untenable, 
for  in  the  case  of  deserted  granaries,  or  if  the  ants 
are  restrained  from  entering  their  granaries,  the 
seeds  begin  to  sprout,  a  proof  positive  that  the 
power  of  growth  is  not  destroyed,  but  merely  hindered 
for  a  season.  The  necessity  for  the  action  is  obvious, 
for  else  the  seeds  would  have  to  be  rapidly  con- 
sumed at  stated  periods  and  be  frequently  renewed. 

Of  late  years  harvesting  ants  have  been  also 
observed  in  America.  The  agricultural  ant  of 
Texas  {Myrmica  Atta  barbara]  not  only  stores  seeds, 
especially  those  of  a  kind  of  grass-like  rice  (Aristida 
stricta),  the  so-called  "  ant-rice,"  it  maintains  clean 
disks  of  ground  round  the  entrance  to  its  nest,  a 
marvellous  work  considering  the  size  of  the  labourer, 
and  the  rich  soil  and  hot  climate.  Many  of  the  disks 
are  not  perfectly  clean,,  usually  round  the  edge  a 


FOOD  OF   INSECTS 


57 


growth  of  ant-rice  scrupulously  free  of  all  weeds 
is  permitted,  and  the  produce  of  this  crop  is 
carefully  harvested  at  the  right  time  of  year,  an 
arrangement  than  which  none  could  be  more  con- 
venient. Two  other  ants,  the  one  peculiar  to  Florida 
(Pogonomyrmex  crudelis)  and  the  mound-raising 
Occident  of  the  great  American  plains  (P.  occidentals}, 
are  likewise  believed  to  be  extensive  harvesters. 

In   England  as  yet,  and   in   countries  of  the  same 


i  iii  ill  Hill 

MfiHifi  i  ! 

i  iS  :*  -1 1  n  ", 

a\\M  I 

i  !> 


FIG.   4.  —  View  of  honey-bearers  as  seen  in  natural   site 
clinging  to  the  roof  of  a  honey-room  ;  from  McCook. 

or  of  colder  temperature,  harvesting  ants  have  not 
been  found.  Perhaps  the  difficulties  in  the  way  of 
hoarding  seed  in  good  condition  in  the  damp  climate 
of  Northern  Europe  would  prove  insurmountable. 
The  food  of  European  ants  consists  chiefly  of 
insects  and  other  small  creatures  which  would 
not  keep  fresh,  and  of  sweet  secretions,  vege- 
table and  animal.  Yet  in  a  way  European  ants  are 
provident,  seeing  that  they  can  obtain  a  meal  at  will 


58  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

from  the  aphides  and  other  ant-cows  that  hybcrnate 
along  with  them.  Vegetable  honey  they  have  not 
learnt  to  preserve,  probably  because  their  young  do 
not  heed  confinement  in  cells,  like  the  larva?  of  the 
honey-bee.  But  on  the  whole  the  disproved  maxim 
of  the  uselessness  of  storage  of  food  by  ants  holds 
good  of  the  English  species,  which  succumb  to  sleep 
more  or  less,  and  require  little  or  no  nutriment  during 
the  cold  winter  months. 

When  the  sun  is  up,  and  everything  is  gay  and 
bright,  and  around  all  nature  seems  quivering  with 
eager  motion  and  activity,  we  are  apt  to  imagine  that 
we  see  before  us  the  whole  population  of  the  insect 
world.  In  reality  a  multitude  as  vast  shun  the 
glare  of  day,  and,  like  the  votaries  of  fashion,  quit 
their  couch  and  rouse  into  thorough  wakefulness  at 
the  sober  hour  of  twilight,  when  their  more  vulgar 
brethren  have  retired  to  rest.  The  "painted  butterfly," 
the  "  fervent  bees/'  the  "  quivering  nations"  of  flies, 
bask  in  the  sunshine  and  search  for  food.  But  after 
the  sun  has  sunk  many  moths  emerge  from  hiding, 
the  shard-born  beetle  with  drowsy  hum  sallies  forth, 
and  numerous  others  of  its  kind ;  and  the  gnats  begin 
to  wing  their  airy  flight,  and  hunt  down  their  living 
prey  with  a  bloodthirsty  and  relentless  ferocity, 
totally  at  variance  with  the  aspect  of  things  so  fragile 
and  so  smalj.  Some  larvae  too  are  night-feeders,  but 
to  the  generality  the  time  for  food  seems  usually  a 
matter  of  indifference,  and  they  eat  apparently  with 
little  intermission  both  night  and  day. 

In  manifold  variety  of  form  the  mouth  or  feeding 
apparatus  of  insects  leaves  that  of  all  other  animals 


ii  FOOD  OF  INSECTS  59 

far  behind.  It  differs  widely  in  the  various  orders, 
it  differs  in  the  families,  it  does  not  always  remain 
constant  throughout  the  lifetime  of  the  individual, 
often  there  is  an  absolute  dissimilarity  between  the 
mouth  of  the  larva  and  that  of  the  perfect  insect. 
The  mouth  parts  may,  however,  be  broadly  divided 
into  two  kinds  :  those  made  up  of  mandibles  or  jaws 
for  comminuting  food,  and  those  forming  a  haustellum, 
or  instrument  for  the  suction  of  liquids  without  distinct 
manducatory  organs.  This  difference  of  structure 
affords  a  natural  opportunity  for  separating  the 
Insecta*  into  two  great  tribes  or  sections — the 
Mandibulata  and  Haustellata,  or  mandibulate  and 
suctorial  groups. 

It  is  possible  to  reduce  the  vast  differences  of  the 
jaws  and  eating  apparatus  to  a  still  more  elementary 
basis  of  structure.  From  this  point  of  view  the 
mouth  of  an  eating  or  mandibulate  insect  is 
very  instructive.  Take  that  of  a  beetle  or  grass- 
hopper. It  consists  chiefly  of  six  parts,  of  which 
four  arc  lateral  and  disposed  in  pairs,  the  other 
two  are  opposed  in  the  opposite  direction,  thus  :': 
There  is  the  labrum,  or  upper  lip  ;  on  either  side  are 
the  first  pair  of  jaws,  or  mandibles  ;  then  come  a 
second  pair  of  jaws,  the  maxillae  ;  and  finally,  below 
the  mouth  is  a  lower  lip,  or  labium,  articulate  with 
the  chin-piece.  The  curved  articulated  appendages 
with  which  the  maxillae  and  labium  are  externally 
provided  are  known  respectively  as  the  maxillary 
and  labial  palpi.  In  the  jaws  of  many  larvae, 
of  a  caterpillar  for  example,  the  form  of  the 
mouth-parts  is  almost  precisely  identical.  The  upper 


60  ROMANCE  OF  THE   INSECT  WORLD     CHAP. 

lip  is  well  grown,  the  mandibles  arc  powerful,  the 
lesser  maxillae  arc  present,  and  behind  these  is  the 
labium  or  inferior  lip.  And  as  in  the  beetle  and 
grasshopper  when  they  arc  perfect,  the  maxillae 
and  labium  of  the  immature  caterpillar  are  in 
general  furnished  each  with  a  pair  of  palpi  or  feelers. 

Let  metamorphoses  go  on,  and  the  leaf-eating 
caterpillar  becomes  a  sucking  butterfly.  A  more 
pronounced  example  of  the  Haustellata  tribe  could 
not  be  given,  and  its  dainty  feeding  organs  seem  to 
have  nothing  in  common  with  the  coarser  apparatus 
of  mandibulate  insects,  or  with  the  early  larval  condi- 
tion of  its  own  mouth.  In  a  butterfly's  mouth  the 
only  apparent  structures  are  a  more  or  less  long 
slender  trunk  or  tube,  and  two  scale-like  feelers  or 
palpi  situated  below  it.  By  removing  the  fine  hairs 
and  dense  clothing  of  scales  from  the  front  of  the 
head,  a  small  transverse  lamina*  is  seen,  and  its 
relative  position  determines  it  to  be  none  other  than 
the  upper  lip  that  was  discovered  in  the  caterpillar, 
although  it  is  marvellously  changed  since  then.  Con- 
tinuing the  investigations,  a  morsel  of  skin  is  observed 
on  either  side  and  beneath  the  lip,  and  judging,  as  in  the 
previous  instance,  by  position,  the  bits  of  skin  are  the 
remnants  of  the  once  strong  biting  mandibles.  Beneath 
these  is  the  conspicuous  trunk,  bearing  at  its  base  two 
small  palpi,  the  presence  of  which  leaves  no  room 
for  doubt  that  the  trunk  is  formed  of  the  altered 
maxillae  of  the  caterpillar.  Below  all  is  the  labium, 
supporting  large  instead  of  the  formerly  small  palpi. 
Examination  thus  reveals  the  fact  that  the  three 
pairs  of  mouth-organs  of  the  caterpillar  are  all 


ii  FOOD  OF   INSECTS  61 

present  in  the  butterfly,  though  in  a  very   different 
condition  of  form. 

This  wonderful  continuity  of  structure  throughout 
the  lifetime  of  a  butterfly,  in  its  change  from  a 
mandibulate*  larva  to  a  sucking  perfect  insect,  shows 
that  the  mouth-apparatus  of  every  insect,  of  the 
Haustellata  and  Mandibulata  alike,  is  founded  on  the 
one  self-same  plan.  The  best  "  all-round  "  or  typical 
development  of  the  head  and  appendages  is  to  be 
found  in  mandibulates,  as  a  whole  in  the  beetle 
family  (Coleoptera).  In  Haustellata  the  deviation 
from  the  type  is  enormous,  but  it  consists  merely  in 
the  modifications  of  certain  parts,  which  are  more  or 
less  developed  in  each  order  in  accordance  with  the 
general  habits  and  instincts  and  modes  of  life.  In 
mandibulates  in  the  carnivorous  and  omnivorous 
families,  whose  habits  require  great  strength,  either 
in  obtaining  food  or  in  the  construction  of  their 
nests,  the  mandibles  are  the  most  important  of  the 
oral  organs  and  the  most  largely  developed.  In 
Haustellata,  whose  food  and  modes  of  life  are  en- 
tirely different,  the  mandibles  lose  their  importance 
and  become  atrophied,  and  their  office,  now  altered 
in  its  character,  is  performed  by  the  maxillae  and 
labium.  The  development  of  these  parts  is  so  great 
that  they  have  become  almost  or  entirely  the  sole 
means  of  taking  food,  whereas  in  the  higher  forms 
of  insects  it  is  only  of  secondary  importance. 

The  transformations  of  the  structures  of  the 
mouth  of  bees  and  flies  are  quite  as  wonderful.  Into 
these  changes  we  must  not  enter.  Of  the  three 
kinds  of  insects,  in  fact  of  all  insects  without  ex- 


62  ROMANCE  OF  THE   INSECT  WORLD     CHAP. 

ception,  Lepidoptera  hold  the  highest  rank  as 
regards  special  adaptation  to  flowers.  They 
take  little  thought  for  their  young,  and  the  mouth 
has  been  free  to  adapt  itself  to  the  easiest  possible 
winning  of  a  floral  liquid  diet.  Many  perfect 
insects  have  similar  tendencies  as  to  food,  but  have 
been  hampered  with  additional  desires.  The  adapta- 
tion is  attained  by  the  astonishing  development  of 
the  maxillae,  to  the  almost  total  abortion*  or  suppres- 
sion of  the  rest  of  the  mouth-parts.  The  atrophied 
condition  of  the  now  useless  organs  affords  a  beautiful 
illustration  of  the  law  that  in  proportion  as  the  func- 
tions of  an  organ  become  suspended,  or  are  not 
required,  by  the  employment  of  other  parts,  the  organ 
itself  deteriorates  and  becomes  useless,  and  perhaps 
entirely  disappears. 

The  maxillae  are  modified  to  take  food  in  a  liquid 
state,  and  still  further  the  food  is  produced  in  ex- 
tremely inaccessible  situations — in  the  deep  hidden 
chalices  or  nectaries  of  flowers.  Thus  they  assume 
the  shape  of  an  elongated,  slender,  and  flexible 
sucking-tube.  Each  maxilla  is  transformed  into  an 
immensely  long  rounded  filament,*  convex  on  the 
outer  surface,  concave  on  the  inner  side,  and  the  tube 
is  formed  by  the  close  approximation  of  the  two 
organs.  Throughout  almost  the  entire  length  of  both 
filaments  one  or  more  large  tracheal  vessels  run,  which 
are  connected  with  the  tracheae  of  the  head.  They 
divide  into  a  number  of  minute  ramifications  as  they 
approach  the  extremity  of  the  organ,  but  have 
no  communication  with  the  external  surface.  The 
presence  of  these  vessels  has  given  rise  to  the  idea 


II  FOOD  OF  INSECTS  63 

that  each  maxilla  is  hollow  in  its  interior,  for  when 
the  tube  is  cut  across — it  is  best  to  cut  it  towards  the 
basal  end — it  appears  to  be  made  up  of  three  small 
tubes,  two  lateral  ones  encompassing  a  central  tube 
between  them.  The  inner  or  concave  surface  of  the 
maxillae  which  forms  the  tube  is  lined  with  a  very 
smooth  membrane.  In  some  species  the  extremity 
of  each  maxilla  is  furnished  along  its  anterior  and 
lateral  margin  with  a  great  number  of  minute  papillae 
arranged  in  two  rows  ;  to  judge  from  their  structure 
and  other  circumstances,  they  may  probably  be 
regarded  as  organs  of  taste.  Among  other  curious 
things  the  tube  possesses  some  stiff,  sharp-pointed 
appendages  along  the  inner  anterior  margin  of  each 
maxilla,  in  the  shape  of  hooks  of  marvellously  small 
size.  When  the  proboscis*  is  extended  they  are  be- 
lieved to  inosculate  with  each  other,  the  hooks  of  the 
one  side  with  those  of  the  other,  just  like  the 
dove-tailing  of  joiner's  work,  and  to  serve  to  unite 
together  the  two  halves,  so  that  they  form  the  anterior 
surface  of  the  canal. 

With  this  exquisitely  simple  mechanism  butterflies 
are  able  to  probe  to  the  bottom  of  the  most  variously 
formed  flowers,  and  to  drain  their  honey.  Not  even 
the  nectar  of  the  long  narrow  bells  of  the  Marvel  of 
Peru  or  of  the  trumpet-shaped  honeysuckle  is  safe 
from  their  pliant  trunks,  hidden  treasure  that  they 
could  never  have  had  the  opportunity  of  tasting  had 
they  retained  the  short  and  more  primitive  biting 
jaws.  In  the  state  of  rest  the  tube  is  spirally  coiled 
up  like  the  mainspring  of  a  watch  in  front  of 
the  head  in  small  and  convenient  compass,  and  lies 


64  ROMANCE   OF  THE  INSECT  WORLD     CHAP. 

partly  concealed  and  defended  between  the  labial 
palps.  It  can  be  brought  forward  in  an  instant, 
straightened  out,  and  darted  downwards  in  obedience 
to  the  bidding  of  its  owner.  In  regard  to  length 
it  varies  in  the  different  genera  and  species,  show- 
ing all  degrees  from  the  proboscis  of  the  Bomby- 
cidae,  that  take  little  or  no  food,  in  which  it  is  almost 
imperceptible,  to  that  of  Sphinx  ligustri  and  the 
Humming  Bird  Hawk  Moth  of  South  America  (Macro- 
glossa  titati),  the  trunks  of  both  of  which  are  about 
two  inches  long.  In  butterflies  and  many  of  the 
Noctuidae  they  are  about  the  same  length  as  the 
body.  The  Sphingidse  are  remarkable  for  not  alight- 
ing on  the  flower  that  they  propose  to  rob,  they  poise 
on  the  wing  before  it,  and  rapidly  dip  into  its  well- 
like  honeyed  cups,  without  crumpling  a  petal. 
Having  extracted  its  sweetest  contents,  they  hasten 
away  on  their  violent  flight  to  another  blossom. 

The  manner  in  which  the  honey  is  conveyed  by  the 
trunk  to  the  mouth  has  been  explained  to  be  by 
capillary*  attraction.  This  opinion  is  probably  in- 
correct, since  the  ascent  of  the  fluid  along  the  tube  is 
not  gradual  and  regular,  as  would  be  the  case  were  it 
occasioned  by  this  action.  The  liquid  is  as  it  were 
pumped  from  the  flower,  sometimes  in  full  stream  for 
one  or  two  seconds  ;  then  the  motion  falls  off  and 
becomes  slower  and  slower,  indicating  distinct  in- 
tervals between  each  draught  or  ascent  of  the  fluid. 
The  phenomenon  appears  to  be  due  partly  to  the 
undulations  and  contractions  of  the  sides  of  the  tube 
occasioned  by  the  action  of  its  transverse  muscles, 
which  continue  in  action  so  long  as  the  insect  is  feed- 


II  FOOD   OF   INSECTS  65 

ing.  This  agency  is  assisted  in  great  measure  by  the 
lateral  canals,  or  tracheal  vessels  of  the  organ.  The 
butterfly  at  the  instant  that  it  alights  upon  a  flower 
makes  a  forcible  expiratory  effort,  by  which  the  air  is 
removed  both  from  the  tracheae  of  the  proboscis  and 
from  those  with  which  they  are  connected  in  the  head, 
and  at  the  moment  of  applying  its  proboscis  to  the 
food  it  makes  an  inspiratory  effort,  dilating  the  tube, 
and  the  food  is  carried  along  it  quickly  to  the  mouth 
to  supply  the  vacuum  produced,  without  any  inter- 
ruption of  the  function  of  respiration.  By  this  com- 
bined agency  of  respiration  and  muscular  action,  we 
can  understand  how  a  butterfly  is  enabled  to  extract 
in  a  moment  the  honey  from  a  flower  while  hovering 
over  it.  This  it  certainly  would  be  unable  to  do  so 
rapidly,  were  the  ascent  of  the  fluid  dependent  on  the 
action  of  the  muscles  of  the  proboscis  alone.1 

Vegetable-feeding  insects  have  little  or  no  difficulty 
in  procuring  food.  All  nature  lies  before  them,  and 
unerring  instinct  is  a  guide  that  never  fails  or  falters 
in  directing  them,  by  flight  or  foot,  to  the  substance 
constituting  their  proper  aliment.  It  is  only  under 
extraordinary  circumstances,  in  face  of  the  unwonted 
destruction  of  plants  or  when  the  numbers  of  these 
tribes  are  unusually  increased,  that  they  ever  perish 
from  starvation.  The  carnivorous  species  experience 
a  harder  struggle  for  existence.  They  are  exposed  to 
the  dangers  of  deficiency  and  deprivation,  but  fortun- 
ately they  are  frequently  endowed  with  the  faculty  of 
enduring  long  abstinence.  The  kind  of  food  they  take 
leads  them  to  employ  a  variety  of  methods  in  supply- 

1  Newport. 

F 


66  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

ing  their  wants.  A  large  proportion  attack  their  prey 
by  open  violence,  which  is  a  clumsy  and  unsportsman- 
like mode  at  best.  Or  they  surprise  insects  by  hiding 
behind  a  stick  or  stone,  affording  concealment  until 
their  approach.  The  predacious  hypocritical  "  praying 
Mantis  " — so  called  because  the  posture  that  it  assumes 
is  supposed  to  resemble  the  attitude  of  a  person  at 
prayer — feigns  sleep  or  death.  But  a  few  species 
have  acquired  far  higher  art  in  providing  their  susten- 
ance. They  have  recourse  to  artifice  and  strata- 
gem. This  is  in  itself  a  fact  of  great  singularity, 
and  the  instruments  by  which  these  carnivora  take 
their  prey  are  admirably  adapted  to  the  end  in 
view. 

The  Ant-Lion  (Myrmeleo  fonnicaleo)  may  be 
adduced  as  an  interesting  example.  It  is  endowed 
with  little  talent  as  far  as  its  powers  of  body  are 
concerned,  but  that  which  it  has  it  turns  to  good 
account.  As  a  larva  it  is  wholly  carnivorous,  and 
shows  preference  for  smart  able-bodied  insects. 
Besides  it  is  an  epicure,  spurning  all  food,  however 
great  its  hunger,  unless  it  be  fresh  caught  and  killed, 
so  to  speak  by  its  own  hand.  To  look  at  it  one 
would  laugh  at  its  pretensions  to  sport.  In  form  it  is 
short,  flat,  squat,  and  excessively  clumsy,  its  body  is 
soft  and  fleshy,  its  motion  is  sluggish,  its  legs  are 
slender  and  feeble,  its  pace  is  absurdly  slow  ;  moreover, 
it  can  merely  walk  backwards.  What  luck  could  this 
creature  have  in  the  chase  ?  Neither  could  it  succeed 
in  obtaining  food  by  lying  in  wait  for  its  prey  exposed 
since  its  jaws  are  so  ferocious  in  appearance  as  to 
incline  every  insect  to  give  it  respectful  berth.  Its 


II  FOOD  OF  INSECTS  67 

object  is  to  conceal  itself,  to  do  which  it  adopts  a 
well-laid  plan,  for  though  it  appears  inert  and  help- 
less it  is  no  bungled  performance  of  nature  as  some 
foolish  persons  would  have  us  to  believe.  On  the 
contrary,  its  structure  is  exactly  what  is  required  to 
render  it  competent  to  capture  living  and  active 
delicacies. 

Choosing  a  fine  light  sandy  soil,  little  exposed 
except  to  the  sun,  and  generally  in  the  neighbourhood 
of  trees  where  ants  are  likely  to  have  set  up  house, 
the  Ant-Lion  vigorously  proceeds  to  construct  its 
snare.  It  begins  by  pushing  itself  backwards  in  a 
circular  direction  so  as  to  trace  a  shallow  furrow  vary- 
ing from  one  to  three  inches  in  diameter.  A  succession 
of  these  furrows  is  formed  one  within  the  other,  each 
being  of  course  smaller  than  the  previous  one,  and  the 
larva  with  its  broad  shovel-like  head  scoops  up  and 
throws  out  the  sand  beyond  the  limits  of  its  precincts. 
By  this  means  a  conical  or  funnel-shaped  pit  is  at  last 
completed,  of  no  great  depth  but  with  very  loose  sides. 
The  insect's  labour  being  over,  it  ensconces  itself  at  the 
bottom  of  the  trap  in  the  sand,  leaving  its  enormous 
jaws  alone  exposed  and  widely  extended.  Here  it 
sits  in  crafty  motionless  vigilance,  in  wait  for  what 
may  come. 

Ants,  like  monkeys  and  children,  are  distinguished 
for  an  insatiable  curiosity,  and  should  one  spy  the  cavity 
when  it  is  abroad  on  the  out-look  for  food  it  would 
never  hesitate  to  approach  the  edge.  Its  satisfaction 
seals  its  doom.  It  gets  a  glimpse  of  the  ogre,  and  in 
vain  it  endeavours  to  retreat,  for  the  treacherous  sand 
gives  way  beneath  its  weight,  and  the  hapless  thing 

F  2 


68  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

goes  rolling  down  into  the  greedy  outstretched  jaws 
of  the  fortress's  Giant  Grimm,  and  a  sharp  bite  soon 
puts  an  end  to  its  existence.  In  a  short  time 
it  is  sucked  dry,  and  the  dead  and  withered 
carcase  is  flung  from  the  pit,  with  an  odd  jerk  of  the 
Ant-Lion's  head,  in  order  to  leave  the  trap  unen- 
cumbered and  ready  for  future  conquest. 

The  victim  does  not  tamely  resign  its  life  to  its 
captor  without  attempting  to  save  itself.  A  plucky 
ant  is  incapable  of  cowardly  conduct  of  the  sort.  But 
it  will  be  readily  perceived  that  the  more  frantic  are 
its  endeavours  to  elude  its  fate  by  scrambling,  the 
greater  is  the  displacement  of  the  yielding  sand,  its 
movements  become  more  and  more  impeded,  it  is 
overpowered,  and  slowly  but  surely  driven  within 
reach  of  the  murderous  jaws.  That  the  Ant-Lion  in- 
tentionally aids  in  bringing  about  the  result  by  dashing 
showers  of  sand  at  the  struggling  insect  is  probably 
somewhat  of  an  exaggeration,  for  one  can  hardly  credit 
it  with  flinging  the  pellets  with  any  definite  aim.  The 
captive  in  its  struggles  must  cause  a  quantity  of  sand 
to  fall  into  the  pit,  and  the  larva  feeling  its  house 
tumbling  in,  instinctively  tosses  it  out.  Some  of  this 
may  hit  the  ant,  and  in  that  case  will  certainly  bring 
it  nearer  the  jaws. 

Naturally  should  a  large  and  unwary  hunting-spider, 
a  wood-louse,  or  perhaps  a  beetle,  pay  the  penalty  of 
inquisitiveness  and  fall  down  the  hole,  the  fight 
between  the  snarer  and  its  prey  waxes  fiercer  and 
more  prolonged.  These  prisoners  have  no  idea  of 
surrendering  at  discretion.  They  are  sore  at  their 
own  folly,  indignant  at  being  betrayed,  and  in  their 


II  FOOD  OF  INSECTS  69 

furious  exertions  to  find  release  they  send  down  the 
sand  in  torrents,  which  fills  up  the  pit,  rendering  its 
sides  far  less  steep  and  therefore  easier  to  surmount,  for 
a  powerful  insect  is  better  able  to  withstand  such  an 
avalanche  than  a  tiny  ant  Then  ensues  a  battle  royal, 
the  one  opponent  fast  bringing  down  the  sand  which 
the  other  as  determinedly  ejects,  being  bent  on  keep- 
ing itself  free  and  on  restoring  its  house  to  its  pristine 
neatness.  Sometimes  a  load  flung  by  the  Ant-Lion 
strikes  the  retreating  creature  unawares,  and  it  loses 
its  balance  never  to  regain  it,  giving  the  larva  just  the 
opportunity  that  it  needed  to  grasp  it  in  its  terrible 
sickle-shaped  mandibles.  Sometimes  the  captive 
becomes  exhausted  before  the  Ant-Lion  and  allows 
itself  to  be  caught ;  and  sometimes,  though  rarely,  the 
onslaught  ends  in  victory  on  the  former's  part,  and 
it  succeeds  in  making  good  its  escape.  In  any  case 
the  pit  has  suffered  such  damage  that  its  owner  does 
not  spend  time  on  rearranging  and  repairing  it,  but 
abandons  it,  and  starts  on  a  fresh  series  of  excavating 
operations. 

In  this  manner,  burrowing  in  the  earth  and  catching 
living  prey,  the  larva  lives  until  it  is  full-grown  and 
fed.  The  early  immature  period  lasts  for  about  two 
years.  It  then  retires  under  the  sand,  and  spins  a 
cocoon  of  silk  mingled  with  sand,  and  after  the  lapse 
of  a  few  weeks  is  transformed  into  the  winged  and 
perfect  state.  The  adults  are  not  in  the  least  like  the 
larvae.  It  would  be  hard  to  conceive  a  more  complete 
contrast,  and  were  the  two  forms  placed  side  by  side 
no  one  unacquainted  with  the  circumstance  would 
believe  them  to  be  but  two  stages  of  the  same  insect. 


70       ROMANCE  OF  THE  INSECT  WORLD      CHAP.  n. 

The  perfect  Ant-Lion  is  very  elegant  and  handsome, 
of  a  dark  grey  colour  with  yellow  spots.  Its  large 
transparent  wings,  four  in  number,  are  ornamented 
with  black  marks.  In  appearance,  in  fact,  it  bears 
many  points  of  resemblance  to  the  dragon-fly. 


CHAPTER  III 

HERMIT     HOMES 

Methods  of  formation  of  homes  constitute  remarkable  phase  of 
habits  and  economy  of  insects — A  home  necessary  by  reason 
of  nature  of  life  of  insects — Habitations  of  solitary  insects 
for  their  young — Solitary  bees  — Solitary  wasps — Galls — 
Habitations  of  solitary  larvae  for  own  use — Homes  of  solitary 
architects  being  perfect  insects  for  own  use  and  also  for 
that  of  their  young  —Trap-door  and  other  spiders, 

OF  all  the  phases  of  the  habits  and  economy  of  the 
insect  world,  none  present  more  remarkable  pecu- 
liarities, and  are  calculated  to  arouse  deeper  feelings 
of  interest  and  appreciation,  than  the  methods  that 
these  little  beings  employ  to  provide  themselves  with 
homes.  We  regard  with  admiration  the  architecture 
of  the  nests  of  various  birds,  we  yield  the  palm  to  the 
villages  of  the  beaver  among  the  structures  of  quad- 
rupeds, but  for  the  acme  of  indefatigable  industry, 
perseverance,  and  ingenuity,  we  must  look  to  the 
habitations  of  the  tiny  insects.  The  very  nature  of 
an  insect's  life  renders  a  home  more  absolutely  neces- 
sary to  it  than  to  almost  any  other  creature.  During 
all  its  immaturity,  to  leave  its  perfect  stage  entirely 


ROMANCE  OF  THE  INSECT  WORLD      CHAP. 


out  of  the  question,  it  would  obviously  be  particularly 
open  to  dangers  of  weather  and  natural  enemies.  But 
here  the  most  powerful  of  its  instincts  steps  in  to  its 

aid,  the  instinct  that  has 
for  its  object  preservation 
of  the  species.  Gifted  with 
what  seems  almost  mira- 
culous foresight,  many  in- 
sects, at  the  expense  of 
incalculable  labour,  prepare 
a  home,  comprising  not 
only  an  abode  but  a  store- 
house of  food,  where  their 
offspring,  which  they  may 
or  may  not  be  destined  to 
see,  and  whose  habits  are 
entirely  unlike  the  parents', 
may  in  safety,  as  complete 
as  possible,  pass  through 
the  whole  series  of  infantile 
helplessness,  and  emerge 
from  it  to  take  their  place 
in  and  cope  with  the  world, 
only  when  they  have  at- 
tained to  the  perfect  form. 
This  instinct  is  in  other 
cases  exercised  by  insects 
for  their  own  accommoda- 
tion, for  their  larval,  pupal,  or  imago  conditions  ;  the 
habitations  being  merely  refuges  or  shelters,  or  afford- 
ing board  in  addition  to  lodgment.  For  these  purposes 
.some  burrow  subterranean  galleries  in  the  ground,  some 


FIG.  5.  —  Profile  view  of  nest  of  a 
Mining  Bee  {Andrena  vicina, 
Smith),  which  builds  her  nest  in 
grassy  fields,  (a)  Oldest  cell  contain- 
ing pupa  ;  (b  b)  cells  containing  larvae  ; 
(c)  cell  containing  pollen-mass,  and 
egg ;  GO  the  most  recent  cell  con- 
taining a  freshly  deposited  pollen- 
mass  ;  (e)  the  beginning  of  a  cell  ; 
(/)  the  level  of  the  ground  ;  from 
Packard. 


in  HERMIT  HOMES  73 

excavate  different  parts  of  vegetation,  some  build 
houses  of  mud,  clay,  or  sand  ;  some  of  leaves,  bits  of 
stick,  grass  and  shells  ;  some  roll  up  leaves  with  art- 
ful care,  and  dwell  therein;  some  construct  homes  of 
excretions  from  their  own  bodies.  In  fact,  the  variety 
of  these  admirable  contrivances  is  nearly  infinite ; 
and  many  for  proportionate  size  and  solidity,  in  com- 
plexity of  arrangement,  and  the  complete  manner 
that  they  subserve  the  intention  of  formation,  may 
very  well  be  compared  with  the  structures  of  reasoning 
man  himself. 

In  this  chapter  it  is  proposed  to  deal  with  the 
habitations  of  insects  living  in  a  state  of  solitude,  and 
built  each  by  a  single  individual,  leaving  the  social 
communities  which  unite  in  the  labours  of  construc- 
tion to  be  dealt  with  later  on.  The  latter  class  are 
better  known,  perhaps,  because  they  are  more  strik- 
ing on  a  general  view  ;  but  intimate  acquaintance 
with  both  leaves  it  a  difficult  matter  to  decide 
which  kind  exceeds  the  other  in  wonder  and  attrac- 
tiveness. 

We  are  all  acquainted  with  the  proverbial  busy- 
ness, the  arrangements  and  policy  of  the  ordinary 
hive  bee,  for  the  care  and  rearing  of  its  young.  With 
like  object,  and  carried  out  with  incomparable  art  and 
activity,  are  the  homes  of  many  of  its  wild  and 
solitary  relatives.  Among  these  bees  there  is  no 
special  laborious  worker,*  and  since  the  male  is  an 
equally  idle  member  of  society  as  the  drone  of  the 
hive,  the  duty  of  providing  for  the  wants  of  the  future 
brood  devolves  solely  on  the  mother.  Awakening 
from  her  winter  sleep,  she  loses  no  time  in  fulfilling 


74  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

her  mission.  She  has  to  select  the  site  of  the  house 
that  is  to  be,  and  to  fashion  it;  to  discover  and  collect 
nourishment,  and  stock  it  in  her  cells,  in  quantity 
sufficient  for  the  proper  development  of  the  larvae,  no 
less  and  no  more,  but  just  enough.  She  lays  her 
eggs,  and  shortly  after  dies.  If  any  fighting  with 
enemies  has  to  be  done  while  her  operations  are  in 
progress,  she  it  is  who  does  it,  so  her  position  in  life 
is  no  enviable  sinecure. 

A  group  of  these  bees  is  popularly  called  the 
Miners,  a  name  fancifully  bestowed  upon  them  by 
Reaumur  to  indicate  the  character  of  their  labours. 
They  are  little  creatures  (Andrena),  but  in  spite  of 
diminutive  proportions  they  are  admirable  burrowers, 
driving  their  tunnels  into  the  ground  or  masonry 
to  a  depth  of  eight  or  ten  inches.  The  soil  they 
select  is  often  hard,  such  that  an  ordinary  pocket- 
knife  makes  no  impression  upon  it,  as  a  well-trodden 
pathway  baked  by  the  sun  ;  occasionally  they  choose 
loose  sand.  Usually  the  burrow  is  dug  in  a  perpen- 
dicular direction  for  several  inches,  when  it  takes  a 
sudden  turn,  and  forms  a  rounded  chamber.  Here 
the  bee  deposits  a  store  of  pollen  *  mixed  with  honey, 
and  lays  a  single  egg.  Creeping  outside  she 
closes  the  orifice  securely  with  the  material  she 
has  expelled  in  excavation,  leaving  the  egg  to  hatch 
and  the  young  to  come  to  maturity  and  escape 
in  due  season.  Some  members  of  this  genus,  and  of 
Halictus,  save  themselves  the  trouble  of  making  a 
number  of  separate  burrows.  They  add  short  sup- 
plementary chambers,  not  more  than  an  inch  or  so 
long,  from  the  sides  of  the  first  and  main  shaft,  and 


in  HERMIT  HOMES  75 

opening  into  it.  In  each  is  placed  an  egg  and  its 
food.  All  the  inmates,  therefore,  though  they  lie 
secluded  one  from  the  other,  emerge  from  their 
nursery,  when  their  time  comes,  by  a  common 
entrance  (see  Fig.  5). 

The  Carpenters  are  solitary  bees  so  called  from  the 
circumstance  of  their  working  in  wood  ;  technically 
they  are  termed  Xylocopa,  a  word  that  literally 
means  a  "  wood-cutter."  As  far  as  we  are  aware, 
none  of  the  genus  are  indigenous  to  this  country,  but 
they  are  scattered  over  all  the  warmer  regions  of  the 
world.  A  trunk  or  branch  of  a  tree  answers  their 
purpose,  and  they  are  particularly  partial  to  old 
posts,  or  wood  railings,  and  to  the  wood-work  of 
houses  which  has  become  soft,  because  beginning  to 
decay.  They  are  never  averse  to  adopting  any  ready- 
made  hole  that  they  may  come  across,  provided  it  is 
not  too  large;  they  even  refurbish  up  old  nests 
deserted  since  a  former  season's  occupation.  Xylocopa 
violacea  may  be  taken  as  typical*  of  the  race,  a  lovely 
creature,  larger  than  the  largest  humble-bee,  with 
brilliant  blue-violet  coloured  wings  and  a  black 
velvety  body,  a  native  of  Southern  Europe.  The 
female  appears  in  the  early  spring,  and  at  once  seeks 
a  spot  to  commence  her  arduous  undertaking.  Its 
selection  is  evidently  a  matter  of  moment  and  con- 
siderable time  is  spent  in  repeated  and  thorough 
investigation  ere  she  fixes  upon  the  wood.  An  upright 
piece  is  usually  decided  upon,  and  with  her  powerful 
jaws  she  begins  a  severe  process  of  boring.  For 
about  the  depth  of  an  inch  she  works  obliquely  down- 
wards, suddenly  the  course  is  altered,  and  she 


76  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

proceeds  perpendicularly  and  parallel  to  the  sides  01 
the  wood,  until  a  tunnel  is  sunk,  of  a  length  no  less 
than  twelve  or  fifteen  inches,  and  perhaps  half  an  inch 
wide.  As  though  this  remarkable  exploit  were  not 
enough,  where  the  diameter  will  admit  of  it,  some- 
times three  or  four  of  these  cylindrical  tunnels  are 
excavated  side  by  side,  a  task  which  takes  several 
weeks  of  incessant  labour. 

One  would  judge  the  nest  to  be  now  complete  and 
ready  for  the  progeny  ;  but  no,  much  more  remains 
to  be  accomplished.  It  is  necessary  for  the  proper 
development  of  the  offspring  that  each  should  have 
a  separate  apartment,  and  be  supplied  with  its 
appropriate  quantity  of  food.  Having  finished  the 
bore  to  perfection — it  is  made  absolutely  clean, 
and  smooth,  and  regular,  as  though  chiselled  by 
a  joiner — and  having  deposited  a  single  egg  at 
the  bottom  along  with  a  ball  of  pollen  and 
honey,  the  bee  covers  this  over  with  a  ceiling  at  the 
height  of  nearly  an  inch  up  the  tube.  Where,  you 
may  ask,  does  she  obtain  her  material,  and  how  is 
this  partition  constructed  ?  During  her  excavation, 
the  quantities  of  fibres  detached  were  carefully  stowed 
away  in  a  neat  little  heap  at  a  short  distance  from  the 
nest,  and  sheltered  from  the  action  of  the  wind.  Here 
then  is  the  wherewithal  that  she  stands  in  need  of. 
With  particles  of  this  sawdust,  cemented  together  with 
her  own  natural  glue  and  to  the  sides  of  the  tunnel 
she  lays  the  foundation  of  the  partition  in  the  form  of 
a  narrow  annular  ring.  Being  hardened,  it  affords 
support  for  another  ring  along  its  interior  edge  ; 
thus  the  orifice  is  gradually  contracted,  and  is 


Ill 


HERMIT  HOMES 


77 


closed  with  a  circular  plate.  Though  the  mass  is 
made  up  of  these  fragments,  it  is  almost  flat  and 
solid,  and  exhibits  the  appearance  of  as  many  con- 
centric circles  as  there  have  been  pauses  in  the 
work.  It  looks  not  unlike  the  annual  zones  in  a 
cross-section  of  a  tree,  or  a  slice  cut  through  the 


FIG.  6. — Nest  of  an  Australian  Carpenter  Bee  (Lesfis  bombylans). 

middle  of  an  onion.  This,  the  ceiling  of  the  first  cell, 
serves  as  the  floor  of  the  second.  In  the  latter 
apartment  another  egg  is  lodged  and  is  furnished  with 
nourishment,  and  receives  a  ceiling.  In  this  manner 
the  bee  continues  until  the  hole  is  divided  into  ten 
or  twelve  chambers,  each  with  its  egg  and  pollen 


ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

(see  Fig.  6),  when  she  closes  the  entrance,  shutting  all 
well  in  lest  the  contents  should  fall  victim  to  some 
unscrupulous  enemy. 

Obviously  a  considerable  interval  of  time  must 
supervene  between  the  laying  of  the  first  and  the  last 
egg,  while  the  bee  is  engaged  in  the  herculean  labour 
of  building  up  the  various  successive  cell-partitions — 
ring  upon  ring,  particle  by  particle — and  in  pro- 
visioning the  occupants  of  the  intervening  cells, 
involving  long  toil  and  diligent  search.  Naturally  the 
lowermost  egg  must  turn  into  grub,  and  pupa,  and 
perfect  insect,  long  before  that  finally  deposited. 
What  then  becomes  of  it  ?  Its  mandibles  are  not 
strong  enough  to  pierce  a  passage  out  through  the 
wood.  It  is  impossible  that  it  can  gnaw  its  way 
through  the  eleven  superincumbent  cells  to  the 
original  entrance  without  damaging  their  immature 
inmates  ;  and  equally  impossible  that  it  can  remain 
imprisoned  till  they  one  and  all  have  effected  their 
escape.  The  mother  provides  against  this  con- 
tingency. She  constructs  not  only  one  point  of 
access  to  her  dwelling,  at  the  farther  end  she  likewise 
makes  a  lateral  horizontal  opening,  a  kind  of  back- 
door, and  chokes  it  with  sawdust  paste,  which  being 
soft  will  readily  yield  to  the  tender  jaws  of  her 
offspring.  Through  this  door  the  first-born  emerges 
into  day,  as  in  fact  does  each  insect,  one  after  the 
other  in  succession  in  priority  of  development  ;  for 
by  an  exquisite  arrangement,  every  grub  when  about 
to  turn  to  pupa  places  itself  in  its  cell  head  down- 
wards, and  thus  in  a  position  eventually  to  break- 
open  the  cell  in  that  direction. 


ih  HERMIT  HOMES  79 

The  Mason  bees  of  Reaumur  belonging  to  the  genera 
Osmia  and  Chalicodoma  are  remarkable  for  the 
singular  variety  of  their  architecture,  or  it  would  be 
nearer  the  truth  to  say  that  they  are  gifted  with 
remarkable  power  of  adaptation  to  circumstances, 
and  vary  the  details  of  their  operations,  through  all  of 
which  runs  one  undeviating  plan.  Their  structures 
are  elaborate,  and  they  exercise  peculiar  care  as  to 
the  materials  used,  each  species  selecting  a  particular 
substance  ;  the  site  of  the  home  is  also  subject  to 
much  fluctuation.  Differing  from  all  others — this 
applies  especially  to  the  Osmia — in  having  their 
hind  legs  unsuited  for  the  gathering  of  pollen,  they 
achieve  the  collection  of  food  by  a  multitude  of 
stiffish  hairs  on  the  rings  of  the  lower  part  of 
the  abdomen.  One  of  the  commonest  mason  bees, 
the  large  and  massive  Chalicodoma  muraria,  or  in 
plain  English  the  "  stone  house,"  a  name  derived 
from  its  building  capabilities,  is  a  builder  in  the 
ordinary  sense  of  the  word,  for  its  homes  are  not  of 
the  more  primitive  burrow  type,  but  are  erections  and 
of  true  masonry.  On  a  rock,  or  stone,  or  wall  of 
sunny  aspect,  they  may  constantly  be  seen,  irregular, 
oblong,  or  egg-shaped  masses,  looking  to  the  casual 
observer  like  so  many  splashes  of  mud  which 
had  been  thrown  against  the  wall  and  had 
become  hardened.  Suppose  the  bee  to  have 
chosen  the  site  of  her  future  dwelling,  as  with 
all  others  a  matter  for  deliberation.  Off  she 
flies  to  a  spot  where  suitable  building-stuffs  are 
obtainable,  and  with  her  mandibles  collects  sand  and 
small  stones,  and  glues  them  with  her  viscid  saliva  to 


8o  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

a  few  grains  of  earth,  adding  little  quantity  to  little 
quantity  until  a  pellet  is  cemented,  the  size  of  small 
shot.  The  ball  of  mortar  being  formed,  is  borne  off 
in  her  jaws  and  fixed  on  the  place  determined.  When 
she  deems  sufficient  material  laid  she  mixes  all  the 
earth,  and  completes  a  cell  about  an  inch  long  and 
half  an  inch  broad.  She  enters  and  anxiously  smooths 


FIG.  7.— Clay  nest  of  a  Solitary  Wasp  (Eumenes)  in  early  stage  ;  from  Natal. 

it,  she  stocks  it  with  a  cake  of  pollen  and  honey,  and 
lays  an  egg  in  the  midst,  then  it  is  walled  over. 
Other  cells  are  similarly  erected  close  by,  up  to  the 
number  of  twelve  or  more.  Their  order  of  deposition 
is  not  regular  ;  they  may  be  parallel  to  the  founda- 
tion, perpendicular  to  it,  or  at  every  conceivable 
angle  of  inclination.  The  building  is  not  yet 
finished,  for  the  group  receives  a  sort  of  roof  or 


in  HERMIT  HOMES  Si 

general  covering,  composed  of  coarser  grains  of 
sand  than  those  hitherto  entering  into  the  composi- 
tion. One  more  provision  must  be  made  for  the  well- 
being  of  the  precious  sojourners.  A  crevice  that  was 
left  open  from  each  cell  to  the  exterior  surface  when 
the  final  wall  was  added  is  now  stopped  up  with 
rather  soft  sand,  easily  penetrated  by  the  feeble  jaws 
of  the  young. 

These  bees  appear  to  keep  a  sharp  look-out  for  the 
ruins  of  any  last  year's  nests  that  afford  possibility  of 
repair,  and  re-making  as  good  as  new.  Finding  an  old 
home  they  go  vigorously  to  work  upon  it  ;  the  cells 
are  swept  clean  of  all  debris  that  has  accumulated — 
the  skins  of  larvae,  cocoons,  and  what  not — any  holes 
and  imperfections  are  attended  to,  and  the  chambers 
victualled  and  closed  up.  Laziness  even  brings 
the  masons  to  dishonesty.  They  will  unlawfully 
intrude  into  a  house  in  course  of  erection,  the 
possession  of  another,  and  fight  desperately  to  re- 
tain the  prize.  Some  Osmiae  adopt  the  simple  and 
less  onerous  plan  as  compared  with  the  labours  of 
Chalicodoma  of  placing  their  cells  in  decaying  wood, 
or  in  the  stems  of  the  blackberry,  the  rose,  and  other 
shrubs,  or  within  straws,  as  the  industrious  and  tiny 
Chelostomes.  One  species  merely  attaches  a  number 
of  balls  of  pollen,  each  with  an  egg,  to  the  under  sur- 
face of  some  flat  stone.  The  larvae  when  full-fed  spin 
their  cocoons  on  the  spots  which  the  pollen  balls  pre- 
viously occupied.  Osmia  bicolor,  a  species  indigenous 
to  southern  Europe  and  found  in  England,  utilises 
abandoned  shells  of  garden  snails  as  ready-made 
burrows.  Strangely  enough,  the  last  laid  eggs,  in  the 

G 


82  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

cells  at  the  mouth  of  the  shell,  produce  males,  which  are 
developed  before  the  female  insects,  who  inhabit  the 
end  of  the  whorl.  The  females  therefore  pass  out 
through  the  deserted  male  premises  above  them. 

The  Megachile  are  celebrated  for  the  beauty  and 
singularity  of  their  nests.  This  is  the  most  cosmo- 
politan of  all  the  genera  of  bees  ;  numerous  alike 
in  the  tropics  and  the  colder  latitudes,  extending  as 
far  northwards  as  Hudson's  Bay.  Their  peculiarity, 
whence  is  derived  their  generic  title,  literally  signi- 
fying "  large-muzzled,"  lies  in  their  long  and  powerful 
mandibles,  and  with  these  instruments  the  species 
dubbed  the  "  Leaf-cutters "  perform  the  clever  feat 
that  their  name  implies.  Under  the  popular  term  are 
included  the  British  and  all  the  known  European 
specimens.  These  agree  in  the  habit  of  making 
curious  burrows  for  their  young,  in  the  earth  or  in 
wood,  lined  with  cuttings  of  leaves,  or  the  petals  of 
flowers,  abstracted  from  plants  with  wonderful  pre- 
cision and  accuracy. 

M.  centuncularis,  a  little  bee,  is  endowed  with 
striking  intelligence,  though  it  is  by  no  means  remark- 
able to  look  at,  like  many  another  clever  creature, 
for  Nature,  it  would  seem,  is  ever  loth  to  cumulate  her 
choicest  gifts,  and  generally  balances  any  lavish  sup- 
ply of  blessing,  physical  or  mental,  by  corresponding 
deprivation  of  the  quality  opposed  to  that  bestowed. 
The  bee  usually  begins,  but  she  is  capricious  in 
choice  of  site,  by  excavating  a  cylindrical  tunnel  in 
tolerably  solid  earth.  It  is  bored  in  a  perpendicular 
direction  for  a  few  inches,  and  afterwards  enlarged 
into  a  horizontal  chamber  of  good  size.  Within  the 


in  HERMIT  HOMES  83 

latter,  starting  at  the  bottom  and  progressing  up- 
wards, eight  to  ten  cells  are  constructed,  composed 
entirely  of  portions  of  leaf,  like  a  file  of  thimbles,  the 
small  and  convex  end  of  each  fitting  well  into  the 
large  and  open  mouth  of  the  cell  previous.  Ten  or 
twelve  pieces  of  leaf  of  different  shapes  are  cut  and 
carried  to  the  bottom  of  the  gallery,  and  there  twisted 
and  folded  one  within  the  other,  so  as  to  form  a  pretty 
funnel-shaped  cone  from  a  quarter  to  a  third  of  an 
inch  long,  narrower  at  the  closed  extremity  than  at 
the  orifice.  The  pieces  are  always  placed  so  that  no 
two  joinings  come  together,  the  middle  of  one  scrap 
lies  over  the  margins  of  two  bits  immediately  below, 
strengthening  the  whole  fabric.  Making  up  a  ball  of 
pollen  and  honey  the  bee  places  it  inside,  and 
with  it  an  egg.  Once  more  recourse  is  had  to  the 
rose,  and  a  fragment  of  leaf  is  taken  off  so  exactly 
circular  that  a  pair  of  compasses  would  not  do  it 
more  nicely,  and  of  a  diameter  fitting  precisely  the 
cell's  mouth.  Into  this  the  morsel,  is  thrust  with  its 
convexity  turned  downwards  ;  a  second  piece,  a 
third,  sometimes  a  fourth,  are  added,  to  obviate  the 
faintest  possibility  of  oozing  of  the  honey.  The  slightly 
concave  surface  of  this  lid  receives  the  follow- 
ing cell  which  is  completed  in  like  manner,  and 
gradually  the  series  is  built  up.  All  being  finished, 
endeavour  is  made  to  hide  the  entrance  to  the  shaft 
with  the  earth  expelled  to  form  it,  and  to  such 
good  purpose  that  no  trace  is  left  of  this  marvellous 
work. 

The  bee,  to  obtain  her  building  material,  rests  firmly 
on  the  edge  of  a  leaf,  usually  so  that  it  passes  between 


84  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

her  legs.  With  her  strong  mandibles  she  quickly 
cuts  out  the  roundish  portion  she  requires,  as  with  a 
pair  of  scissors,  turning  upon  a  pivot  with  her  feet  ; 
and  lest  its  weight  should  carry  her  to  the  ground, 
just  before  the  last  fibre  is  severed  she  balances  her- 
self in  the  air  for  flight,  and  at  the  moment  it  parts 
bears  it  off  in  her  jaws  in  triumph. 

Anthocopa  papaveris,  the  "  abeille  tapissiere"  ol 
Reaumur,  as  though  fascinated  by  the  brilliant  colour, 
fixes  its  choice  of  cell-lining  upon  the  common  scarlet 
poppy.  It  is  small,  of  a  velvety  black,  ornamented  with 
white  downy  hairs  on  the  margins  of  the  segments  of 
the  abdomen.  Its  burrows  are  perpendicular  holes  in 
dry  and  sandy  soils,  perfectly  cylindrical  at  first, 
but  swelled  out  below  in  the  shape  of  a  Florence 
flask.  The  sides  the  bee  stamps  firm  and  smooth  ; 
then  portion  after  portion,  to  the  number  of  three  or 
four  layers,  is  cut  from  the  poppy,  each  morsel  as  it  is 
introduced  into  the  cell  being  pressed  and  straightened 
against  the  walls,  to  take  out  every  curl  and  wrinkle 
from  the  delicate  tissue.  The  honied  provision  and 
the  solitary  egg  being  committed  to  this  cosy  apart- 
ment, the  upholsterer  carefully  folds  in  the  free  ends 
of  the  petals,  a  necessary  precaution  owing  to  the 
nature  of  the  soil,  to  prevent  the  encroachment  of  the 
grains  of  sand.  This  done,  the  rest  of  the  hole  is 
stopped  with  earth. 

Some  of  the  exotic  *  species  of  Megachile, 
as  M.  lanata  and  M.  disjuncta,  common  to  India, 
form  tubes  of  agglutinated  particles  of  sand  or 
clay  independently  of  a  burrow.  They  also  fill  up 
the  hollows  of  tree-stems  with  clay  cells,  instead  of  a 


Ill 


HERMIT  HOMES 


lining  of  leaves,  built  end  to  end  in  long  lines,  but 
with  very  little  cohesion.  The  tenacity  with  which 
the  clay  adheres  to  the  wood,  however,  is  remarkable, 
and  probably  it  is  inspissated  with  some  glutinous 
substance  ejected  by  the  insect. 

Equal  in  interest  to  the  nests  of  bees,  and  con- 
structed with  similar  purpose,  are  the  homes  of  many 
solitary  wasps,  and  other  so-called  Fossorial  *  Hy- 
menoptera.  However  well-defined  so  far  as  external 
characteristics  are  concerned, 
the  families  have  many  mutual 
resemblances  in  their  habits 
of  life,  though  each  species  has 
its  own  particular  fancies  as 
to  site  of  home,  and  food,  and 
other  details.  Like  bees,  in 
the  adult  state  they  live  on 
honey  and  such-like  vegetable 
fluids,  but  the  larvae  are  flesh- 
feeders,  and  we  see  the  curious 
and  suggestive  sight  of  non- 
carnivorous  mothers  chasing 
and  bringing  down  insect 
prey  for  their  carnivorous  offspring.  One  point  in 
connection  with  this  feeding  deserves  special  mention 
— the  young  must  derive  their  nourishment  not 
merely  from  animal  substances,  but  from  actual  living 
tissues.  Inert,  unarmed,  unable  to  help  themselves, 
or  to  move  from  the  spot  where  they  are  hatched, 
how  can  they  ever  have  living  insects  in  their  power  ? 
the  difficulties  to  be  paved  away  seem  insur- 
mountable. Nature  holds  a  fairy  wand ;  it  is 


FIG.  8. — Pelopseus  Wasp  building 
nest ;  from  Bates. 


86  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

the  mother  who  provides  for  them.  In  captur- 
ing insects  she  does  not  kill  them,  she  inserts  her 
venomous  sting  in  her  victims,  producing  a  long, 
indeed  a  fatal,  lethargy,*  for  the  poison  seems  to 
preserve  the  unfortunate  creatures  from  death  and 
decay.  In  this  condition  she  carries  them  to  her 
cells,  in  this  condition  they  lie,  condemned  to  be 
slowly  eaten  by  the  hymenopterous  larvae.  Let  us 
hope  kind  Nature  deprives  the  luckless  beings  of 
consciousness  in  the  same  moment  that  they  are 
robbed  of  animation. 

The  Fossores  belonging  to  the  genus  Odynerus,  or 
the  False  Wasps,  are  pretty  little  black  things,  striped 
with  yellow,  noted  for  their  agility  and  graceful 
movements.  The  Masons  of  Reaumur  may  constantly 
be  seen  in  this  country  in  great  numbers,  flying  to 
and  fro  over  a  hard,  sandy,  or  gravelly  bank  exposed 
to  the  sun,  boring  their  tunnels  and  storing  them 
often  with  the  green  larvae  of  a  weevil,*  of  which 
as  many  as  fifteen  or  sixteen  may  be  put  in  one  cell. 
They  raise  a  fanciful  cylindrical  tube  over  the  mouth 
of  their  burrow  ;  when  finished,  it  often  projects  from 
the  soil  no  less  than  two  or  three  inches.  It  is 
formed  of  pellets  of  earth  arranged  in  circles 
one  over  and  in  front  of  the  others,  with  small 
intervening  spaces  left  open  between  the  masses, 
giving  it  the  appearance  of  filigree  work.  For  the 
greater  part  of  its  length  it  is  upright,  but  towards 
the  top  is  carried  downwards  to  describe  a  slight  curve. 
The  use  of  this  vestibule  is  doubtful ;  perhaps  it  may 
prevent  the  incursions  of  artful  parasites,  who  may 
fear  to  enter  so  long  a  defile.  Whatever  the  object 


tit  PERMIT  HOMES  87 

may  be,  it  is  a  temporary  one.  Present  only 
while  the  victualling  is  going  on,  and  the  eggs  are 
laid,  subsequently  this  entrance  to  the  gallery  is 
pulled  down,  and  constitutes  the  material  that 
goes  to  fill  up  the  lip  of  the  hole. 

Eumenes  coarctata,  the  only  British  example  of  its 
genus,  an  odd-looking  wasp,  has  the  first  segment  of 
its  abdomen  drawn  out  to  form  a  decided  foot-stalk, 
so  that  the  abdomen  appears  joined  to  the  thorax  as 
by  a  bit  of  fine  black  wire.  Its  nests  are  small, 
globular,  and  vase-like,  built  of  mud,  and  fastened  to 
the  stems  of  various  plants,  the  common  heath  being 
the  greatest  favourite.  Each  contains  one  cell,  and 
is  the  habitation  of  one  occupant.  E.  pomiformis 
affixes  her  nests  to  walls.  E.  petiolata,  conica,  and 
esuriens,  Indian  species,  seem  to  prefer  the  wood- 
work of  houses,  such  as  door-  and  window-frames 
and  posts,  and,  where  the  locality  is  suitable,  some- 
times a  succession  of  cells  will  be  constructed  side  by 
side,  often  more  than  a  foot  in  length.  The  nest  of 
petiolata  is  the  size  of  a  pigeon's  egg.  Whatever  the 
exigencies  of  the  situation,  the  Eumenes  strives  to 
retain  the  spherical  form  of  the  edifice  and  the 
recurving  brim  (see  Fig.  7). 

The  Sphegidae,  Pompilidae,  and  Bembecidae,  are 
popularly  classed  together  as  the  Sand-wasps.  As 
their  name  denotes,  they  love  to  form  homes  in  sandy 
earth,  where  they  lay  eggs,  and  stock  them  with 
living  insects,  rendered  powerless  by  their  poisonous 
stings.  The  well-known  Sphex,  the  typical  genus  of 
the  Sphegidse,  is  scattered  over  the  greater  part  of 
the  world  ;  the  English  species — there  is  but  one — is 


ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

somewhat  common  in  the  eastern  counties.  Am- 
mophila  afford  an  excellent  instance  of  the  ordinary 
manner  in  which  these  insects  prepare  their  burrow. 
It  consists  of  a  long,  narrow  gallery,  opening  into  an 
enlarged  chamber,  a  formation  calculated  to  enable 
the  mother,  after  storing  the  prey  she  has  secured,  to 
regain  the  surface.  She  descends  into  the  tunnel 
backwards,  dragging  her  burden  after  her,  and  were 
it  the  same  size  in  every  part,  there  would  be 
no  room  for  her  to  creep  from  under  the  food,  and  to 
pass  out.  The  genus  Pelopaeus  are  inhabitants 
principally  of  warm  climates.  Many  are  excellent 
masons,  and  may  be  watched  at  muddy  puddles, 
kneading  and  rolling  up  clay  into  spherical  pellets,  and 
carrying  them  off  in  their  mandibles  to  form  the  future 
residences  (see  Fig.. 8).  The  oddest  spots  imaginable  are 
often  chosen  for  their  sites.  Sometimes  a  cell  is 
separately  constructed  ;  sometimes  one  is  placed  over 
another  ;  but  generally  the  nest  is  composed  of 
a  number  of  cells,  built  side  by  side  upon  the 
same  horizontal  line,  each  being  filled  with  food 
and  closed  as  completed.  The  whole  is  covered 
exteriorly  with  a  smooth  coating  of  mud.  The 
mothers  are  bold  and  fearless  hunters,  and  think 
little  of  attacking  strong  and  well-armed  spiders. 
Doubtless  their  sting  is  a  terrible  weapon,  and 
when  once  the  enemy  is  struck,  taken  unawares 
it  may  be,  all  is  over.  But  the  spider,  if  on  the  out- 
look, sometimes  manages  to  cast  its  web-threads  over 
the  Pelopaeus,  and  paralyses  its  movements  ere  the 
fatal  arrow  is  shot.  Soft  plump  spiders,  one  would 
naturally  think,  would  be  chosen  by  the  wasps. 


lit  HERMIT  HOMES  89 

But  in  tropical  America  P.  fistularis  culls  those  be- 
longing to  a  large  group  allied  to  our  common  garden 
spider,  all  possessed  of  hard  shelly  polished  cover- 
ings, not  even  smooth,  but  shooting  out  into  the 
most  fantastic  and  formidable  projections.  The 
genus  Pompilus  rival  the  Sphegidae  in  bravery  and 
cunning  in  catching  prey.  They  also  provide  spiders 
for  their  larvae,  mostly  wandering  kinds  which  never 
make  webs.  In  this  country  where  about  twenty 
species  of  Pompilus  are  known,  they  are  of  small  size 
and  unimposing. 

In  another  class  of  habitation  for  the  young  the 
homes  serve  in  the  dual  capacity  for  the  shelter 
and  the  sustenance  of  the  occupants,  and  though  they 
spring  from  the  mother's  work  they  rise  independ- 
ently of  her  construction.  It  will  be  understood  that 
we  speak  of  galls,  vegetable  excrescences  that  we  all 
know  well.  They  differ  in  appearance,  shapes,  and 
sizes,  and  affect  multitudes  of  plants,  though  the  oak 
is  especially  prone  to  the  attack.  All  parts  of  the 
plant  are  infested  by  them,  the  leaves,  the  buds,  the 
trunk,  the  twigs,  even  the  flowers,  the  fruit,  and  the 
root.  Every  one  has  observed  these  abnormal  growths, 
but  comparatively  few  persons  are  acquainted  with 
the  insects  to  which  they  owe  their  origin,  and  with 
their  young,  for  whose  early  up-bringing  alone  they 
exist. 

The  Hymenoptera  that  produce  galls  constitute  a 
group  by  themselves,  the  Cynipidse,  which  contains 
the  genus  Cynips,  and  others  very  much  like  it. 
Though  they  vary  greatly,  a  striking  family  re- 
semblance runs  through  them  all.  They  have  an 


90  ROMANCE  OF  THE  INSECT  WORLD      CHAt>. 

oblong  and  very  convex  body,  and  the  female  is 
provided  with  a  peculiar  apparatus  for  egg-laying,  the 
ovipositor,  a  slender  hair-like '  tube,  which  when  not 


FIG.  9. — Galls  of  Cynips  insana,  or  Dead  Sea  Apples. 

in  action  is  coiled  up,  spiral  fashion,  within  the 
abdomen.  During  spring  and  summer,  when  vegeta- 
tion is  in  full  sap,  is  the  time  for  depositing  the  eggs. 
Having  selected  a  proper  spot,  the  "fly"  straightens 


in  HERMIT  HOMES  91 

her  ovipositor  and  thrusts  it  instantaneously  into 
the  leaf  or  other  object,  making  a  puncture,  subse- 
quently widened  by -boring.  Into  the  hole  she  drops 
one  or  more  eggs.  To  conclude,  she  spreads  a  slight 
quantity  of  secretion  over  the  wound,  so  irritating  to 
the  plant's  tissues  as  to  alter  their  nature,  and  de- 
velop, but  how  we  know  not,  the  irregular  swelling 
of  the  cellular  structures  that  we  term  a  gall.  Midst 
the  fleshy  chamber  thus  constructed  the  eggs  are 
hatched,  and  the  larvae  live  on  its  interior.  The 
insects  remain  within  the  galls  until  they  have  under- 
gone all  their  changes,  and  emerge,  eating  their  way 
out  into  the  open  air,  upon  their  attainment  to  the 
perfect  form.  Others  escape  as  larvae,  and  burrow 
into  the  earth  for  their  later  metamorphoses. 

Forty-two  or  more  kinds  of  galls  occur  on  oaks  in 
Great  Britain  alone,  but  the  damage  done  to  the  trees 
seems  almost  immaterial.  There  are  the  familiar 
oak-apples,  arranged  usually  several  together  in  small 
clusters  on  the  twigs  and  branches,  irregular  in 
shape,  and  sometimes  of  enormous  size,  the  work 
of  Cynips  terminalis.  These  contain  an  aggre- 
gation of  cellules,  twelve  to  fifteen  or  more,  the 
hermit  habitations  of  solitary  larvae.  From  the 
separate  cells  a  fibre,  as  it  were,  runs  towards  the 
base  of  the  gall.  Probably  these  fibres  are  the 
nervures  of  leaves  which  would  have  sprung  from 
the  bud  in  which  the  eggs  were  laid,  had  not  the 
irritating  fluid  caused  them  to  develop  in  a  new 
manner.  The  well-known  small  oak-apples  found  in 
profusion  on  oak  leaves  are  due  to  the  puncture  of 
Cynips  quercus  folii.  Well  they  deserve  their  popular 


92  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

title  of  cherry-galls,  being  beautifully  coloured,  some 
scarlet,  some  white,  some  red  and  orange,  in  various 
gradations.  Their  surface  is  smooth  and  brightly 
shining;  in  substance  they  are  of  a  soft  pulpy  consist- 
ency, not  unlike  a  gooseberry  or  hot-house  grape. 
In  the  centre  of  the  mass  is  a  solitary  globular 
chamber  containing  a  single  larva  snugly  curled  up. 
The  undersides  of  oak  leaves  are  also  infested  by 
small,  flat,  round,  disc-like  bodies,  the  common 
spangle  galls  of  the  Neuroterus  lenticularis.  They 
sometimes  occur  in  such  quantities,  but  rarely,  as  to 
weigh  the  leaves  and  cause  premature  withering. 
The  elegant  so-called  currant  galls  that  depend  on 
slender  threads  from  the  oak's  catkins  resemble  sparse 
bunches  of  currants.  Their  colour  is  another  reason 
for  their  name,  for  they  are  sometimes  scarlet  and 
sometimes  white. 

The  Rose  Bedeguar,  or  Robin  Redbreast's  Pin- 
cushion, frequent  on  hedge-roses  and  sweet-briars,  is 
formed  by  C.  roses,  an  insect  about  the  fifth  of  an  inch 
long.  She  deposits  her  eggs  towards  the  end  of  May 
or  beginning  of  June,  with  the  result  of  great  swelling 
of  the  stem,  while  the  leaves  are  produced  in 
ordinary  numbers  but  without  cellular*  tissue  between 
the  fibre-vascular*  bundles,  causing  the  exterior  of 
the  fungus-like  growth  to  be  covered  with  numberless 
many-branched,  hair-like  filaments,  the  so-called 
"  moss."  These  galls  attain  their  full  size  on 
the  approach  of  cold  weather.  How  pretty 
they  look  at  the  close  of  summer  tinted  with 
green  and  red.  When  winter  ultimately  sets 
in,  they  lose  all  brilliancy  and  become  uniformly 


in  HERMIT  HOMES  93 

brown.  Although  the  soft  compressible  moss-like 
surface  appears  to  form  the  whole  of  the  gall,  in 
reality  there  is  a  dense  woody  tissue,  within  which 
lie  the  larvae  admirably  protected  against  injury  from 
without.  The  number  of  cells  in  a  Bedeguar  is 
mostly  great.  They  are  usually  restricted  in  size  ; 
larger  dimensions  seem  always  obtained  at  the  ex- 
pense of  solidity  of  the  walls.  Each  cell  contains 
a  single  egg,  and  each  in  its  own  restricted  space 
the  larvse  are  hatched.  In  this  stage  they  remain 
quietly  at  rest  for  the  winter,  quickly  changing  to 
pupae  and  the  perfect  forms  at  the  beginning  of  the 
following  spring.  Should  the  spring  be  cold  the 
"  flies "  do  not  at  once  desert  their  home  on  the 
completion  of  their  metamorphoses,  but  await  the 
arrival  of  propitious  weather.  Then  they  gnaw  their 
way  through  their  abode  and  escape. 

The  gall  nuts  of  commerce,  or  Aleppo  galls, 
used  to  make  ink  and  tinctures  and  whence 
gallic*  acid  is  derived,  affect  the  leaves  and 
twigs  of  an  Eastern  species  of  oak  (Quercus  infect- 
oria*},  abundant  in  Asia  Minor  and  Turkey.  They 
are  remarkably  hard,  and  almost  spherical  and  tuber- 
culated.*  Their  juice  may  be  said  to  be  colourless, 
but  if  it  is  mixed  with  a  solution  of  the  sulphate  of 
iron  or  copperas,  itself  very  pale  green,  the  two  com- 
bined produce  a  fluid  intensely  black,  such  as  the  ink 
in  common  use.  Any  one  may  prove  the  fact  for 
himself,  and  manufacture  ink  on  a  small  scale,  by 
cutting  some  succulent  British  gall  with  a  steel  knife, 
and  he  will  find  his  fingers  stained  as  with  pale  ink 
by  the  action  of  the  iron  on  the  moisture  of  the  gall. 


94  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

The  so-called  Dead  Sea  fruits,  apples  of  Sodom,  or 
Mala  insana  (see  Fig.  9),  grow  on  dwarf  members  of 
the  same  oak  on  the  borders  of  the  Dead  Sea.  About 
them  strange  stories  have  been  told,  and  their  nature 
once  aroused  controversy  amongst  commentators  upon 
Biblical  and  Oriental  literature.  Travellers  use  to 
describe  these 

Dead  Sea  fruits  that  tempt  the  eye, 
But  turn  to  ashes  on  the  lips  ; 

beautiful  to  look  upon  with  their  glossy  deeply- 
purplish  red  surface,  and  as  large  as  good-sized  apples. 
But  when  tasted,  instead  of  the  sweet  juicy  substance 
one  was  led  to  expect  by  the  lovely  exterior,  they  filled 
the  mouth  with  bitter  dry  ashes,  drawn,  so  it  was  said, 
by  the  oak  from  the  ruins  of  three  evil  cities  buried 
beneath  the  bituminous  waves  of  the  Dead  Sea. 
Hence  the  "  fruits  "  were  tangible  evidence  of  the 
cities'  former  existence.  For  many  a  day  this  story 
was  believed  ;  at  length  it  was  dismissed,  the  very 
existence  of  the  "  fruits "  was  denied  as  the  inven- 
tion of  an  Eastern  fable,  in  spite  of  plain  allusions 
to  the  contrary  by  Josephus,  Strabo,  Tacitus,  and 
other  ancient  authors.  Recent  research  proves  the 
main  facts  of  the  case  to  be  correct;  the  inferences 
deduced  fare  badly.  These  "  fruits "  are  galls  of  a 
Cynips  named  by  Westwood  insana.  They  do  not 
belie  the  old  descriptions  of  their  beauty,  and  natur- 
ally they  are  astringent,  more  especially  as  they 
grow  upon  an  oak.  Doubtless  they  will  prove 
sufficiently  so,  if  any  one  care  to  make  the  test, 
as  to  warrant  the  tales  of  the  rough  and  ash-like 


in  HERMIT  HOMES  95 

sensation  they  produced  on  the  palate  in  the  days 
gone  by. 

Cynipidae  are  not  the  only  insects  that  originate 
galls.  In  the  beetle  group  some  of  the  weevils  pass 
their  early  stages  in  swellings  brought  about  by  the 
parents.  The  Cecidomyia  in  the  order  Diptera,  the 
saw-flies,  the  aphides,  the  moths,  and  many  more  are 
likewise  gall-makers. 

No  form  of  habitation  can  be  simpler  and  more 
natural  than  the  burrow,  and  when  it  is  made 
in  seeking  for,  or  in  eating,  food,  the  point  seems 
to  be  reached  at  which  simplicity  of  design  can 
go  no  farther.  Many  an  insect  that  to  see  is  to 
admire — fragile,  beautiful  in  brilliant  colour,  soaring 
in  the  air,  exulting  in  the  sunbeams — indebted  to  its 
own  exertions,  has  passed  the  previous  portion  of  its 
life  thus  hidden  in  the  interior  of  a  tree  trunk,  a 
branch,  a  leaf,  or  a  root,  even  in  fruit  or  in  the  earth, 
feeding  greedily  on  its  surroundings  or  upon  any 
prey  that  might  come  within  its  reach.  In  these  con- 
cealed situations  it  has  entered  upon  its  etherealised 
winged  state,  and  become  equipped  for  its  higher 
position  and  purer  atmosphere. 

Of  this  nature  are  the  homes  of  the  larvae  of  one  of 
the  wasp-like  moths,  Sesia  apiformis.  These  cater- 
pillars are  pale  in  colour,  and  at  a  glance  one  judges 
them  to  be  wood-eaters.  The  eggs  are  laid  on  the 
bark  of  poplar  trees,  and  when  hatched  the  young  at 
once  make  their  way  into  the  interior  of  the  trunks, 
and  eat  out  tunnels  of  considerable  size  for  no  less  a 
period  than  two  years  previous  to  their  metamor- 
phosis into  chrysalides.  For  this  labour  the  grubs 


96  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

are  admirably  adapted,  while  they  are  quite  unsuited 
for  browsing  upon  tender  succulent  *  leaves.  Their 
forcible  jaws  readily  rend  the  dense  woody  tissue  ;  the 
legs  are  small,  so  as  to  prove  no  hindrance  in  the 
narrow  tunnels  ;  and  the  head  is  protected  by  a  hard 


FIG.  10. — A  Sack-bearing  Caterpillar  (Saccophora)  ;  from  Bates. 

and  reddish  integument,  affording  solid  support  for  the 
strong  masticating  apparatus.  Larvae  of  moths  of 
the  family  Hepialidse,  abundant  in  Africa,  America, 
and  Australia,  many  of  them  of  enormous  size,  have 
exactly  similar  habits.  Our  own  country  is  not 
exempt  from  the  ravages  of  the  wood-borers  of 


Ill 


HP:RMIT  HOMES 


97 


Lepidoptera.     One  of  the  most  injurious  to  many  of 
our  timber  and  fruit  trees  is  the  goat-moth  caterpillar 


FIG.  ii. — Metura  Sandersii  from  Australia;  (a  female). 

(Cossus  ligniperdcL],   so-called   from  an  oily  fluid  that 
it  exudes  from  its  mouth  of  a  very  rank  and  pungent 

H 


98          ROMANCE    OF   THE    INSECT   WORLD      CHAP. 

goat-like  odour.  The  caterpillars  are  hatched  in 
crevices  in  the  bark,  and  at  first  they  feed  in  the  bark, 
or  between  that  and  the  wood.  As  soon  as  size  and 
strength  permit,  they  penetrate  into  the  living  tree, 
and  make  galleries  and  chambers,  larger  perhaps  than 
those  of  any  of  our  wood-boring  enemies.  Propor- 
tionately as  the  larva  increases — and  its  growth  is 
amazing — the  diameter  of  its  burrow  becomes  en- 
larged ;  and  since  its  course  is  erratic,  and  it  remains 
in  the  larval  condition  for  fully  three  years,  the  mis- 
chief it  perpetrates  is  great.  During  the  winter,  how- 
ever, it  lies  dormant,  and  does  not  feed,  in  a  cocoon 
ingeniously  constructed  from  wood-chips  roughly 
spun  together  with  silk  thread.  This  nest  is  often 
over  two  inches  long  and  one  in  width. 

The  larvae  of  the  Scarabaeidse,  the  giants  of  their 
order  (Coleoptera),  are  likewise  notable  wood-borers. 
Fortunately  for  us,  for  the  amount  of  vegetable 
matter  that  they  consume  must  be  enormous,  the 
larger  species  live  exclusively  in  countries  where  a 
luxuriant  vegetation  can  best  afford  their  depreda- 
tions. At  home  perhaps  no  wood-boring  beetle  is 
better  known  than  the  little  Scolytus  destructor.  It 
is  destructive,  particularly  to  elms,  both  in  its  mature 
and  larva  states,  and  many  large  trees,  and  even  whole 
forests,  succumb  to  its  attacks.  The  mother  enters 
the  tree  in  search  of  food  ;  and  to  lay  her  eggs  she 
squeezes  herself  in  between  the  bark  and  the  wood, 
where  she  bores  out  a  cylindrical  gallery,  usually 
from  three  to  five  inches  long,  taking  her  about  three 
weeks  to  complete.  Along  the  sides  the  eggs  are  laid 
at  regular  distances  apart,  to  the  number  occasionally 


in  HERMIT    HOMES  99 

of  a  hundred  and  upwards.  She  then  generally  re- 
treats to  the  entrance  and  dies.  As  soon  as  the  larvae 
are  born  they  begin  to  feed.  Urged  by  a  wonderful 
instinct  each  arranges  its  body  at  right  angles  with 
the  parent  gallery,  and  proceeds  to  gnaw  the  wood 
steadily  outwards.  These  side  alleys  become  grad- 
ually larger  to  allow  room  for  the  growing  tenants, 
but  they  all  radiate  from  the  central  tunnel,  and 
rarely  interfere  with  each  other  by  coalescence,  their 
radiation  more  than  keeping  pace  with  their  increasing 
size.  Had  the  grubs  all  started  parallel  with  each 
other  the  tunnels  must  have  joined,  and  confusion 
and  deprivation  of  sufficient  food  would  have  been 
the  consequence.  Full-fed,  the  larvae  turn  to  pupae, 
and  eventually  pierce  the  bark  and  emerge.  Large 
species  of  Calandra  larvae,  some  two  inches  long,  com- 
mit fearful  devastation  in  the  tropics,  boring  into  the 
pith  of  large  trees  and  into  sugar-cane.  South 
America  suffers  similarly  from  the  immense  beetle 
Titanus  giganteus.  In  the  West  Indies,  while  the 
grubs  of  Lamia  amputator  and  an  allied  species  exca- 
vate mimosa  and  acacia  trees,  the  perfect  insects 
complete  the  mischief  of  their  young  by  gnawing 
round  the  branches  in  a  circular  line,  all  except  the 
central  pith.  Sooner  or  later  the  stems  fall  to  the 
ground  by  their  own  weight  or  by  the  force  of  the 
wind.  The  parents'  action,  it  is  presumed,  is  directed 
to  the  prevention  of  a  large  flow  of  sap  into  and 
through  the  branch,  which  might  harm  the  enclosed 
larvae  and  impede  their  metamorphoses. 

The  leaves  of   garden  trees   and  plants,  the  rose 
especially,  are  often  traversed  by  white  winding  lines. 

H  2 


ioo         ROMANCE    OF   THE    INSECT  WORLD      CHAP. 

Upon  holding  a  leaf  so  marked  to  the  light,  the 
tracks  are  perceived  to  be  due  to  the  absence  of  the 
parenchyma  ;  they  are  in  fact  galleries  or  tunnels 
between  the  upper  and  lower  membranes  burrowed 
out  by  larvae,  by  the  laborious  procedure  of  eating 
the  excavated  material  as  they  go.  In  most  cases 
towards  one  end  the  gallery  increases  largely  in 
width,  and  here  the  miner  changes  to  pupa,  and  from 
this  part  flies  when  mature.  The  minuteness  of 
these  insects  is  realised  when  we  consider  that  the 
thickness  of  many  a  leaf  is  not  greater  than  that  of 
this  sheet  of  paper.  Yet  within  this  space  the  larvae 
find  room  to  exist.  It  is  worth  while  to  remember 
that  the  early  states  of  winged  insects  are  always 
large  in  proportion  to  the  imago  condition,  much  of 
the  substance  being  taken  up  by  the  rudimentary 
wings.  Leaf  miners  belong  to  the  orders  Lepidoptera, 
Coleoptera,  and  Diptera,  though  Lepidoptera  furnishes 
by  far  the  greatest  numbers.  These  are  so  minute 
that  they  can  hardly  be  recognised  as  moths,  and 
are  simply  exquisite  gems  of  Nature. 

Amongst  British  Coleoptera,  the  common  green 
tiger  beetle  (Cicindela  campestris)  is  very  interesting 
in  its  habits.  Though  small  it  is  remarkable  for 
fierceness,  while  for  grace  and  beauty  it  challenges 
comparison  with  the  grandest  exotics.  As  a  larva 
it  has  all  the  love  for  slaughter  evinced  by  its  parents, 
but  its  sedentary  tastes  and  bodily  structure,  its 
white  delicate  skin  and  short  legs,  would  seem  to 
preclude  gratification  of  the  desire.  So  far  as  chase 
or  open  assault  is  concerned  it  makes  no  attempt  ; 
it  leaves  warfare  alone,  and  resorts  to  diplomacy. 


in  HERMIT    HOMES  101 

With  its  short  stout  and  spiny  legs  and  powerful 
jaws  it  burrows  out  a  vertical  tunnel  in  the  ground, 
and  its  flattened  head  ejects  the  earth  detached. 
The  tunnel  is  a  foot  long  and  of  a  diameter  ade- 
quate to  admit  of  the  larva  passing  up  and  down  ; 
towards  the  bottom  it  curves  into  a  horizontal 
chamber.  To  make  ready  to  catch  its  prey,  the 
burrower  ascends  to  the  mouth  of  the  opening, 
where  it  fixes  itself  steadily  by  pressing  the  back 
of  its  body  against  the  walls,  its  eighth  segment 
being  developed  into  a  hump-like  projection  which 
carries  a  pair  of  bent  hooks.  Its  head  and  jaws  lie 
perfectly  level  with  the  soil  and  are  hardly  visible, 
so  that  any  insect  will  walk  unsuspiciously  over  them. 
Instantly  at  the  moment  the  larva  feels  the  touch 
its  sickle-like  jaws  are  opened,  it  grasps  the  victim, 
and  drags  it  to  the  bottom.  Or  the  beetle  upon 
becoming  cognizant  of  the  presence  of  the  insect,  slips 
with  great  precipitation  down  the  burrow,  and 
naturally  the  prey  falls  in  after  it  and  is  soon  eaten. 

An  enormous  variety  of  caterpillars,  chiefly  those 
of  moths  of  the  families  Tineina  and  Tortricina, 
make  homes  of  leaves,  which  they  twist  up  and 
roll  and  fold  and  unite  together  to  form  safe 
habitations  and  abundant  supplies  of  food.  The 
genus  Halias,  which  are  very  common  to  France, 
do  infinite  mischief  to  the  vines.  From  the  eggs, 
laid  on  the  top  of  vine  leaves  in  the  middle  of 
summer,  the  caterpillars  are  soon  hatched,  but  they 
do  not  at  once  begin  to  feed,  though  surrounded 
by  abundance  and  the  weather  is  warm,  they  swing 
themselves  by  silken  threads  waiting  to  be  tossed 


102          ROMANCE   OF    THE    INSECT  WORLD      CHAP. 

about  by  the  wind.  By-and-by  the  larva  touches 
some  prop  or  stem  of  the  vine,  when  it  penetrates 
into  cracks  in  the  wood,  or  beneath  the  bark,  and 
hibernates  until  the  late  spring  of  the  following  year. 
Climbing  up  a  stem,  it  now  binds  the  young  leaves 
and  little  bunches  of  grapes  into  a  comfortable  home, 
subsequently  eating  away  the  inside.  Some  cater- 
pillars confine  their  exertions  to  a  single  leaf. 
They  fold  it  longitudinally  and  fasten  the  edges 
with  silk  ;  or  transversely,  attaching  the  point  to 
the  middle  nervure.  Some  roll  it  longitudinally 
others  transversely,  or  part  of  it,  to  make  a  hollow 
cylinder.  So  minute  are  many  of  these  insects  that 
they  cannot  accomplish  the  feat  by  main  force.  Sup- 
pose the  leaf  is  to  be  wrapped  transversely.  Again 
and  again  a  series  of  silken  cables  are  attached  to 
its  point  and  upper  edges,  their  other  ends  are 
fastened  to  the  centre.  Each  cable  in  succession 
is  pulled  and  tightened  by  the  larva's  feet  and  spin- 
neret until  the  structure  bends  over,  when  it  is 
securely  held  in  position  by  fresh  and  shorter  threads. 
In  this  manner  the  work  is  continued  until 
the  leaf  is  rolled  into  the  tubular  form  desired, 
and  the  mechanic  enters  its  home  and  feeds  on 
the  soft  substance  in  almost  perfect  safety.  In  some 
cases  the  provision  it  obtains  is  ample;  but  should  the 
life  in  larval  state  be  long  it  may  be  compelled 
to  construct  other  rolls,  the  nourishment  from  the 
first  roll  being  exhausted. 

One  species  of  leaf-mining  caterpillars  (Coleo- 
phora)  as  soon  as  they  have  tunnelled  a  cavity  in 
the  leaf,  cut  out  the  mined  portion  to  form  a  case, 


in  HERMIT    HOMES  103 

sewing  the  two  sides  together  with  silk.  While  the 
anterior  orifice  is  circular,  the  posterior  end  is  often 
diamond-shaped.  Some  Tinea,  more  saving  of  labour, 
make  the  tubes  at  the  very  edge  of  the  leaf  which 
acts  in  place  of  a  seam.  The  owner  does  not  repair 
or  enlarge  an  old  abode  of  the  kind,  but  having 
eaten  the  best  part  of  it,  the  larva  abandons  it  and 
builds  anew. 

Other  species  of  Tineina  make  homes  at  our  ex- 
pense out  of  bits  of  wool,  hair,  silk,  or  fur,  from  our 
dress  and  household  stuffs,  which  they  delight  to 
gnaw.  The  tube  of  Tinea  tapetzella  is  almost  cylin- 
drical, and  though  rough  exteriorly,  is  daintily  lined 
with  silk  spun  from  the  artificer's  own  mouth. 
When  about  to  turn  to  pupa  the  larva  closes  one 
end  of  the  house  and  suspends  it  bottom  downwards. 
Before  transformation  it  faces  round  inside  the  case, 
directing  its  head  towards  the  end  unattached.  This 
larva  forms  only  one  home,  which  is  altered  from  time 
to  time  as  it  becomes  too  small  by  additions  of 
threads  to  either  extremity.  Should  the  width  need 
enlargement,  the  occupant  cleverly  inserts  new  ma- 
terial into  apertures  made  lengthways  for  the  purpose. 
In  colour  the  case  always  corresponds  with  that  of 
the  substance  from  which  it  is  taken,  and  quite  a 
motley  appearance  may  be  given  it  if  stuffs  of  various 
hues  are  placed  in  the  way  of  the  little  manufacturer. 

These  dwellings  are  surpassed  by  the  building  per- 
formances of  larvae  of  a  genus  of  the  family  Psychidae, 
common  to  America,  Australia,  and  Europe  (sec 
Fig.  n).  Of  all  the  species,  the  House  Builder 
{Oiketicus  Sandersii)  is  perhaps  the  most  remarkable. 


104         ROMANCE   OF   THE   INSECT  WORLD     CHAP. 

The  cases  are  made  up  of  pieces  of  slender  twigs,  laid 
parallel  to  each  other  to  form  hollow  cylinders,  with 
care  and  exactness,  much  like  the  rods  in  old  Roman 
fasces  carried  by  lictors  before  the  consuls  ;  hence  the 
popular  title  of  the  makers  is  Lictor  Moths.  Frag- 
ments of  wood  and  leaves,  morsels  of  straw  or  grass 
or  sprigs  of  moss,  bound  together  by  silk,  are  likewise 
employed.  These  homes  the  inmates  carry  about 
with  them  as  snails  do  their  shells,  the  head  and 
thoracic  segments  alone  protruding  to  permit  them 
to  grasp  the  leaves  and  twigs  or  whatever  they  are 
crawling  over.  The  portion  thrust  forward  is,  however, 
hardly  distinguishable,  and  it  is  very  curious  to  see  a 
tube  moving  along  apparently  of  itself.  As  regards 
large  Psychidae  in  America,  the  cases  depend  far 
beyond  their  bodies  ;  sometimes  the  total  length  is 
as  great  as  from  four  to  five  inches.  If  the  larva 
desire  repose,  it  can  retract  its  head  and  primary 
segments,  and  retire  inside  completely.  To  render 
itself  quite  safe  when  it  is  clinging  to  a  branch,  it 
can  press  the  mouth  of  the  tube  against  the  branch 
so  firmly  that  it  is  closed  effectively  ;  if  detached, 
the  mouth  can  be  drawn  together  by  stout  silken 
threads,  arranged  around  its  circumference.  When 
about  to  become  a  pupa  the  insect  withdraws 
within  the  nest,  and  closes  it  ;  shut  in,  it  prepares 
for  its  pupal  sleep.  The  females  of  Oiketicus  San- 
dersii,  and  of  an  allied  genus,  are  wanting  in  wings, 
almost  in  legs  and  antennae  in  the  perfect  state,  and 
environed  in  the  tubes  they  pass  the  whole  of  their 
existence.  None  but  an  entomologist  would  take 
them  for  mature  Lepidoptera. 


Ill 


HERMIT   HOMES 


105 


Remarkable  residences  built  under  water  by   the 
larvae   of  Caddis   Flies    (Trichoptera)    are    wonder- 


FIG.  12. — Part  of  the  nest  of  a  Trap-door  Spicier  {Nemesict  eleanora) 
with  single  tube. 


fully  like    these    homes    of    Psychidae.      They     are 
composed    of     fine     stems    of    rushes     and     other 


io6         ROMANCE   OF   THE    INSECT  WORLD      CHAP. 

plants,  of  bits  of  stick,  leaves  of  grasses,  minute 
pieces  of  bark  and  wood,  fresh  or  decayed,  of  grains 
of  sand,  or  gravel  or  mud,  of  hay,  and  any  such  debris 
that  may  have  fallen  into  the  water.  Small  fresh- 
water shells,  yet  occupied  by  their  living  inhabitants, 
are  even  affixed  by  the  caddis  to  its  case  by  their 
flat  exterior,  and  the  material  or  materials  are  glued 
together  with  a  waterproof  cement.  The  tubes  tend 
to  assume  the  cylindrical  shape,  and  the  interiors  are 
lined  with  silk.  Sometimes  short  lengths  of  plant 
stems  are  placed  longitudinally  side  by  side,  with 
the  utmost  regularity,  to  form  a  perfect  and  shapely 
cylinder,  perhaps  four  inches  long.  The  morsels 
may  be  wound  spiral  fashion,  or  may  be  dis- 
posed into  a  many-sided  structure,  and  so  on  in 
endless  variety  of  arrangement.  The  larvae  are  each 
provided  with  two  hooks  on  the  soft  skin  of  the 
end  of  the  abdomen,  so  as  to  anchor  itself  firmly  to 
its  house.  When  about  to  undergo  metamorphoses 
they  fix  their  dwelling  to  something,  and  block 
up  the  ends,  not  with  a  solid  stopping,  with  a  kind  of 
open  fence,  which,  while  it  prevents  the  intrusion  of 
enemies,  allows  free  percolation  of  the  water  in  and 
out.  The  adults  may  be  observed  any  evening 
in  summer  flying  about  the  banks  of  streams  and 
marshes.  The  female  enters  the  water  to  lay  her 
eggs,  which  previous  to  this  event  she  keeps  for  a 
short  time  in  a  green  bundle  attached  to  her  body, 
her  object  being  probably  to  expose  them  to  the 
warmth  of  the  sun  before  immersion.  Enveloped  in 
a  glutinous  mass  they  adhere  to  an  aquatic  plant,  or 
to  a  stone.  Upon  an  insect  being  hatched  it  im- 


in  HERMIT   HOMES  107 

mediately  forms  its  tube,  for  the  protection  of  its 
soft  delicate  body  and  in  view  of  its  carnivorous 
disposition.  When  the  transformations  are  almost 
complete,  it  eats  its  way  through  the  end,  and 
leaves  its  pupal  skin  by  flight  at  the  surface 
of  the  water.  Larger  kinds  crawl  up  the  stems 
of  aquatic  plants  before  abandoning  the  pupal 
envelope.  A  few  caddis  worms  make  immovable 
habitations,  fixed  to  the  spot  whereon  they  were 
constructed.  The  grub  is  then  compensated  by  larger 
range  of  movement  ;  its  abdominal  claspers  are  of 
much  greater  length  proportionately,  allowing  it  to 
extend  itself  to  some  distance  from  the  entrance. 

Some  moths  (Hydrocampidae)  are  aquatic  during 
their  larval  period.  A  common  species  in  France 
fashion  homes  for  themselves  out  of  two  pieces  of 
leaf,  sewn  as  it  were  together  with  a  little  silk, 
whence  their  heads  and  thoracic  segments  appear,  as 
in  the  caddis. 

Among  the  habitations  constructed  by  solitary 
architects,  being  perfect  insects,  for  their  own  accom- 
modation, some  of  the  simplest  are  those  of  the 
mole  and  field  crickets.  The  odd-looking  mole 
cricket  (Gryllotalpa  vulgaris)  is  one  of  the  largest 
insects  in  England,  stouter  and  stronger  than  any, 
and  like  its  namesake  it  is  fierce  and  irascible,  and 
exceedingly  voracious.  In  shape,  and  also  in  many 
of  its  habits,  it  is  the  very  counterpart  of  the  mole. 
Its  appearance  testifies  to  its  mode  of  life.  The  body 
is  almost  cylindrical,  the  tibiae  *  of  the  fore-legs  are 
short,  broad,  and  flat,  and  as  it  were  fingered,  the 
feet  being  small,  and  almost  hidden  by  the  broad 


loS         ROMANCE    OF   THE    INSECT  WORLD     CHAP. 

palmated  legs  to  prevent  them  being  injured  when 
the  cricket  is  digging.  Armed  with  its  spade- 
like  apparatus,  it  burrows  out  large  excavations 
in  the  ground  to  a  greater  or  less  depth,  vertical 
shafts  with  long  horizontal  galleries  abutting.  As  a 
rule,  it  prefers  loose  and  made  soils,  as  in  kitchen  and 
nursery  gardens  and  vineries.  It  cuts  and  eats 
through  everything  that  comes  in  its  way,  so  that  its 
ramifications  are  a  grievous  source  of  mischief  among 
young  plants  and  flowers  ;  in  fields  they  may  be  of 
certain  use,  the  tunnels  forming  a  kind  of  sub-soil 
drainage.  Like  the  mole,  it  reserves  a  distinct 
chamber  apart  from  its  other  galleries  for  its  young. 
Formed  at  no  great  distance  below  the  surface,  this 
room  is  about  three  inches  in  diameter,  and  nearly 
one  inch  high,  very  neatly  made,  and  its  walls  are 
carefully  levelled  and  hardened  to  resist  the  action  of 
the  rain.  Here  the  eggs  are  laid  secure  from  all 
ordinary  foes,  and  no  doubt  their  hatching  is  effected 
by  the  sun's  warmth,  which  will  penetrate  to  the 
slight  depth  at  which  they  lie.  Secluded  in  its  home, 
the  insect  passes  its  life  in  a  state  of  absolute 
solitude,  issuing  forth  at  nightfall,  when  alone  it  dis- 
ports itself  on  its  wings.  It  never  soars  to  any  great 
height. 

In  character  and  habits  Ac/ieta  campestris  is 
very  similar.  At  night  it  comes  out  and  sits 
just  within  the  entrance  to  its  hole,  chirping 
away  at  its  monotonous  song  for  hours  together. 
Being  wary  and  timid,  it  takes  alarm  at  the  least 
noise,  and  retreats  inside  with  precipitation.  But  it 
is  combative,  and  may  be  drawn  out  by  inserting 


in  HERMIT    HOMES  109 

down  the  tunnel  a  stick  or  straw,  which  it  clutches  as 
in  a  vice.  In  France  children  fasten  a  fly,  or  ant,  to 
the  thread,  or  stick,  that  they  poke  down  the  nest, 
but  this  is  quite  a  superfluous  addition,  for  it  is  anger 
and  not  hunger  that  incites  the  cricket  to  grasp  the 
intruding  object.  The  largest  known  species  (A. 
monstrosa)  are  natives  of  India,  and  make  burrows 
sometimes  three  feet  deep. 

No  solitary  insects  surpass  spiders  in  house-build- 
ing. Many  of  their  homes  are  not  merely  intended 
for  the  rearing  of  their  young,  but  are  homes  in  the 
true  sense  of  the  word,  where  they  reside  day  after 
day,  and  to  which  apparently  they  become  fondly 
attached.  They  consist  chiefly  of  burrows  in  the 
ground.  Even  in  England  we  may  come  across 
little  specimens  tunnelled  out  in  some  sandy  soil, 
and  lined  with  silky  membranous  tubes  to 
prevent  the  earth  from  falling  in.  From  the 
mouth  a  web  is  spread  to  catch  the  prey,  while  the 
hunter  lies  concealed  at  the  bottom,  waiting  for  the 
approach  and  capture  of  victims  in  the  snare  above. 
The  finest  simple  spider  tunnels  belong  to  the 
Mygalides,  a  family  of  the  tropics  that  comprise  the 
gigantic  creatures  of  their  tribe.  Several  species  of 
the  genus  Mygale  have  great  hairy  bodies,  almost 
as  large  as  sparrows,  and  an  expanse  of  limb  no  less 
than  half  a  foot  and  more.  One  very  robust  fellow, 
Mygale  blondii  by  name,  a  great  burrower,  forms 
a  broad  slanting  tunnel  some  two  feet  deep,  and  the 
sides  are  lined  with  a  silken  coating.  This  spider  is 
nocturnal,  and  may  be  seen  at  sunset  occasionally 
at  the  mouth  of  its  den,  keeping  watch  for  passing 


no         ROMANCE    OF   THE    INSECT  WORLD     CHAP. 

delicacies,  which  being  caught  are  destroyed  at 
leisure  in  the  safe  retreat.  Probably  it  seldom 
wanders  far  from  home. 

The  greatest  perfection  of  tubular  nests,  however, 
culminates  with  the  so-called  trap-door  spiders.  For 
beauty  of  workmanship,  for  ingenuity  in  arrangement, 
for  marvellous  cleverness  in  overcoming  difficulty  and 
avoiding  danger,  these  arachnids  *  must  be  assigned  a 
front  place  among  Nature's  handicraftsmen.  They 
inhabit  many  warm  countries,  notably  the  West 
Indies,  the  United  States  of  America,  India,  and 
Australia.  The  typical  nest  is  a  cylindrical  tunnel 
in  the  ground,  beautifully  lined  with  silken  web  and 
protected  by  a  valve  or  lid — "  the  door  " — fitted 
accurately  into  the  frame  of  the  orifice  at  the  surface, 
and  like  our  doors  possessed  of  a  hinge,  upon  which 
it  turns  with  the  greatest  freedom,  allowing  it  to  be 
opened  and  closed  at  pleasure.  Some  of  the  larger 
kinds  of  these  nests;  as  in  the  West  Indies,  are  a  foot 
deep  and  about  an  inch  in  diameter,  and  are  dug  out 
by  the  strong  jaws  of  the  spiders  often  in  a  steep 
bank  of  bare  clay.  The  silken  lining  tube  may  be 
removed  from  the  burrow,  and  is  then  seen  to  be 
double  ;  the  outer  covering  being  comparatively 
strong,  harsh,  and  thick,  and  deeply  stained  of  the 
colour  of  the  earth,  while  the  texture  of  the  inner 
layers  is  very  different,  being  nearly  white  and  soft, 
and  smooth,  the  smoothness,  however,  not  precluding 
certain  irregularities  of  surface,  it  resembles  rough 
and  unsized  paper.  The  door  is  composed  of  the 
same  substance,  and  is  continuous  with  the  tube  for 
about  a  third  of  its  circumference — forming  the  hinge 


Ill 


HERMIT    HOMES 


in 


— or  sufficiently  to  ensure  that  it  does  not  fall  care- 
lessly to  either  side,  but  comes  with  precision  into 
the  mouth  and  closes  it.  Perfect  closure  is  rendered  a 


FIG.  13. — Part  of  the  nest  of  Nemesia  meridionals,  showing  the  surface  door  open, 
and  the  lower  door  pushed  across  so  as  to  close  the  principal  tube.  The 
subsidiary  tube  ends  in  a  cnl-de-sac. 

matter  of  certainty  by  the  aperture  of  the  tube  be- 
ing slightly  recurved  to  form  a  brim  or  lip,  and 
the  interior  surface  of  the  lid  is  a  little  convex. 


112          ROMANCE    OF   THE    INSECT  WORLD      CHAP. 

Exteriorly  it  is  level  with  the  ground,  and  the  silk  is 
coated  with  earthy  particles.  In  fact,  all  trace  of  the 
work  is  completely  obliterated.  Travellers  to  the 
West  Indies  describe  the  alarm  they  at  first  experi- 
enced in  seeing  the  earth  open,  a  little  lid  lifted,  and 
a  formidable-looking  spider  peep  out  of  the  hole. 

These  tunnels  are  seldom  situated  in  flat  ground, 
where  the  door  would  lie  horizontally  when  closed. 
A  sloping  or  nearly  vertical  bank  is  usually  chosen, 
and  the  hinge  is  placed  at  the  highest  side  of  the 
opening,  so  that  the  door  when  pushed  up  on  the 
entrance  or  exit  of  the  owner  falls  to  by  its  own 
weight,  ensuring  concealment  of  the  nest.  The 
edges  of  the  door  are  accurately  adjusted  to  the 
bevelled  lip  of  the  tube,  and  offer  a  certain  degree 
of  mechanical  resistance  to  the  entry  of  an  enemy. 
Should  the  spider  be  at  home  when  his  door  is 
touched,  he  is  made  aware  of  the  impending  danger 
by  the  vibrations  of  the  silken  threads.  Speeding  to 
the  scene  of  action,  he  hooks  his  hind  legs  to  the 
lining  of  the  lid,  his  fore-legs  to  the  side  of  the  tunnel, 
and  turning  upon  his  back  resists  the  threatened 
invasion  with  all  his  might.  Excessively  bold  and 
courageous,  he  defends  his  territory  with  the  greatest 
pertinacity;  nothing  short  of  actual  violence  will  in- 
duce him  to  desert  it.  In  some  nests  a  row  of  minute 
holes,  as  though  pricked  with  a  fine  needle,  is  pierced 
round  the  free  edge  of  the  lid,  another  row  lies 
immediately  within  the  margin  of  the  tube.  It  has 
been  suggested  that  these  help  the  spider  in  holding 
the  cover  against  attack  ;  in  Mr.  Gosse's  opinion  they 
serve  to  admit  light  and  air  to  the  dwelling,  and  are 


in  HERMIT  HOMES  113 

indispensable,  owing  to  the  density  of  the  lining 
material  and  the  tightly-fitting  lid.  The  row  round 
the  edge  of  the  tube  may  be,  as  it  were,  a  stock  in 
reserve  in  case  of  accident,  should  the  lid  holes 
happen  to  become  effaced  with  particles  of  the  sur- 
rounding earth. 

Some  trap-door  nests. of  the  south  of  Europe  (see 
Figs.  12  and  13)  have  thinner  doors,  less  tough  and 
coarse  in  texture,  and  frequently  they  are  not  wedged 
into  the  top  of  the  tube  like  a  stopper,  they  simply  rest 
over  it.  Often  the  excavation  is  amidst  moss  and  other 
low  undergrowth,  securing  safety  in  obscurity  of  site. 
The  lower  extremity  may  end  in  a  short  spur-shaped 
enlargement.  Sometimes  a  subsidiary  branch  is  dug 
obliquely  upwards  from  the  middle  to  the  surface, 
where  it  is  lightly  closed  by  a  few  silk  threads ;  usually 
this  shoot  is  a  mere  cul-de-sac  (see  Fig.  13).  A 
hanging-door  exists  at  the  junction  of  the  two  tubes  ; 
and  at  the  depth  of  two  or  three  inches  down  the 
main  one  a  door  of  the  same  kind  may  be  found. 
If  an  enemy,  a  parasitic  fly,  for  example,  force  its 
way  into  the  nest  by  the  principal,  or  the  sole  en- 
trance, as  the  case  may  be,  the  spider  is  believed  to 
press  up  the  last-mentioned  door,  leaving  the  intruder 
to  all  appearances  to  an  empty  domicile.  Should  this 
manoeuvre  fail,  and  the  hunter  be  not  deceived  by  the 
trick,  the  spider  can  dodge  into  the  branch,  and 
draw  the  second  door  to  behind  him.  Where  the 
branch  extends  to  the  surface,  if  needs  be,  he  can 
evacuate  his  premises  and  escape. 

Certain  spiders"  (Lycosides)  raise  a  cylindrical 
hollow  tower  over  their  burrow,  much  like  an  ordin- 

I 


ROMANCE  OF  THE  INSECT  WORLD       CHAP. 


ary  bird's  nest  on  a  diminutive  scale,  forming  it  very 
symmetrically  of  bits  of  grass,  leaves,  sticks,  and 
rootlets,  or  of  clay,  little  stones,  and  a  few  stronger 
sticks,  loosely  interwoven  with  silky  secretion  (see 
Fig.  14).  Evidently  it  plays  the  same  part  as  a 
trap-door,  and  contributes  to  the  concealment 
of  the  hole.  On  removing  it  the  shaft  is  found  to 
be  often  twelve  and  fifteen  inches  long ;  in  one 
instance  a  depth  of  twenty-two  to  twenty-three  inches 

was  reached.  It  is 
perfectly  round  and 
perpendicular,  and 
may  widen  out  into 
two  enlarged  cham- 
bers, an  upper  and 
a  lower  one,  but  the 
tunnels  of  many 
ground-spiders  are 
of  the  same  dia- 
meter throughout. 
Both  the  nest  and 
the  tube  may  be 
silk-lined,  or  the  latter  may  be  innocent  of  web  ; 
usually  the  entrance  is  neatly  underwoven  with  this 
substance  mixed  with  sand.  Mrs.  Treat,  an  eminent 
American  naturalist,  describes  another  species  of 
spider  as  establishing  a  dome-like  roof  over  its  tunnel, 
made  up  of  a  canopy  of  web  overlaid  with  leaves, 
blades  of  grass,  and  such  like  matters,  the  whole  being 
securely  fastened  down  except  at  a  place. of  entrance 
and  exit,  which  is  only  discovered  with  the  closest 
scrutiny.  These  spiders  have  the  habit  of  closing  this 


FIG.  14. — Nest  of  the  Turret  Spider  (Lycosa  areni- 
cola\  United  States,  America. 


in  HERMIT  HOMES  115 

opening  in  the  autumn  season  for  the  space  of  two  or 
three  weeks,  in  order  to  elude  the  raids  of  the 
fossorial  wasps,  who  are  then  engaged  in  provision- 
ing their  young.  The  wasps  run  over  the  ground, 
peering  into  every  nook  and  cranny,  and  should  one 
alight  upon  a  nest  unbarricaded,  down  it  goes 
and  returns  with  the  inmate,  rendered  powerless  by  its 
poisonous  sting.  During  the  winter  the  doors  are 
likewise  hermetically  sealed. 

Unlike  most  of  its  kind  the  spider  Argyronetra 
aquatica  is  aquatic,  or  rather  amphibious,  and  habit- 
ually spends  the  greater  portion  of  its  time  in  the 
watery  element,  constructing  its  home,  and  surround- 
ing itself  with  the  atmospheric  air  essential  for  respir- 
ation. It  may  be  found  in  various  parts  of  England 
—Cambridge  is  a  favourite  locality — in  rivers  and 
pools  and  ditches  where  the  water  is  calm  and  un- 
troubled. Its  cell  is  composed  of  silk,  and  is  more  or 
less  oval  in  shape  and  about  half  the  size  of  a  pigeon's 
egg,  and  is  suspended  in  a  vertical  position,  the  open 
part  being  directed  downwards.  The  spider  commences 
by  spinning  loose  threads  of  silk  in  different  directions, 
attaching  them  to  the  leaves  of  water-plants — the 
framework  of  her  building  so  to  speak.  Within  these 
supports  she  sets  her  beautiful  transparent  chamber. 
Before  occupation  it  is  necessary  that  it  be  filled  with 
air.  Slowly  but  surely  ascending  to  the  surface, 
assisted  by  a  thread  fixed  to  the  leaf  or  other  house 
prop  below,  and  to  the  outside  of  the  water,  she 
obtains  a  bubble  from  the  atmosphere,  and  imme- 
diately and  quickly  descends  with  it  by  the  same 
route  to  the  bell-shaped  nest.  Having  arrived 

I    2 


u6          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

there,  she  disengages  the  air.  These  journeyings 
are  repeated  perhaps  fourteen  times,  and  at  last 
her  apartment  becomes  full  of  air  to  the  exclusion  of 
water,  the  globules  of  air  having  replaced  the  water. 
Into  the  dome  she  enters,  and  settles  to  rest,  undis- 
turbed by  the  agitations  above,  head  lowermost,  after 
the  manner  of  her  tribe.  The  air  acquired  is 
mechanically  entangled  in  the  tissue  covering  the 
animal's  body,  and  is  held  on  by  the  two  hinder  legs, 
which  are  crossed  over  the  abdomen  at  the  instant 
that  the  bubble  is  seized.  To  this  home  the  spider 
brings  her  prey,  and  in  it  lays  her  eggs,  spinning  a 
white  silken  saucer-shaped  cocoon  for  them,  and 
placing  it  against  the  inner  side  of  the  cell  and 
near  the  top.  The  young  remain  beneath  with  their 
mother  until  they  are  grown  a  little,  and  have  become 
strong  enough  to  form  sub-aquatic  dwellings  on  their 
own  account. 

The  so-called  raft  spider  (Dolomedes  fimbriatus] 
is  amongst  the  largest  of  the  British  species,  and 
the  globular  cocoon,  which  the  female  carries  about 
with  her,  may  contain  as  many  as  several  hundreds 
of  eggs.  The  spider  not  only  lies  in  wait  for  its 
prey,  but  chases  them  like  a  carnivorous  verte- 
brate.* It  pursues  them  on  land,  and  in  the  water, 
on  the  surface  of  which  it  runs  fearlessly.  When 
thus  employed  it  gathers  a  quantity  of  dry  leaves 
and  rubbish,  and  unites  the  collection  together  with 
threads  of  silk  into  a  resting-place  or  raft.  On 
this  the  maker  sits,  and  is  blown  about  by  the 
winds  and  currents.  It  knows  no  lack.  Aquatic 
insects  are  constantly  coming  up  to  the  outer  air  to 


in  HERMIT  HOMES  117 

breathe,  insects  just  completing  their  transformations 
are  acquiring  their  wings  at  the  surface,  and  many 
smaller  and  less  powerful  than  our  hunter  are  abroad 
on  the  water  on  the  same  errand,  to  gain  their  liveli- 
hood. Any  and  all  of  these  make  capital  food  for 
fimbriatus,  who  pounces  upon  them,  and  devours  them 
on  the  raft.  Should  it  see  an  enviable  morsel  at  a 
distance  it  darts  off  the  platform,  returning  to  enjoy 
its  meal.  On  the  approach  of  an  enemy  it  can  pene- 
trate the  water,  and  can  exist  submerged  for  some 
time. 

Lycosa  piratica,  a  closely  allied  species,  also  chases 
its  prey  on  the  water,  but  it  makes  no  raft.  It  like- 
wise is  able  to  descend  below  the  surface,  when  it 
breathes  by  means  of  air  confined  among  the  hairs 
with  which  it  is  clothed. 


CHAPTER  IV. 

SOCIAL   HOMES. 

Diversity  of  method  of  insect  architecture,  its  beauty  and  size — 
The  word  architecture  as  applied  to  this  portion  of  insect 
economy— Societies  of  social  caterpillars— Three  types  of 
nests  of  ants— Home  of  Common  Wood  Ant — external 
conformation — internal  plan — doors — formation  and  regula- 
tion of  society — A  solitary  "  queen  "  as  founder  of  a  colony 
— Singularity  of  wood-ant  in  preference  for  open-air  life 
• — Mason  Ants — Extraordinary  dimensions  of  homes  of 
Saiiba  or  Coushie  Ants — Their  leaf-cutting  propensities — 
Mushroom-growers — Mason  Ants  of  New  World  ;  their 
disks,  roads,  refuse-heaps,  store-rooms,  nurseries,  lum- 
ber closets,  position  as  farmers,  &c. — F.  fuliginosa  and 
other  carpenters — Standing-army  of  Bull's  Horn  Acacia — 
Ants  as  guardians  of  other  plants — Remarkable  pensile 
nests  of  Crematogaster,  Myrmica  Kirbit^  (Ecophylla 
smaragdtna,  &c. 

IN  no  branch  of  insect  work  are  more  admirable 
means  employed  to  bring  about  the  desired  ends,  or 
is  greater  diversity  of  method  found,  than  in  that 
of  insect  architecture.  The  beauty  of  the  buildings 
in  many  cases  is  incomparable,  and  generally 
speaking  the  abodes  attain  a  magnitude  colossal  as 
compared  with  that  of  their  creators.  It  may  be 


CHAP,  iv  SOCIAL  HOMES  119 

exception  will  be  taken  to  the  use  of  the  word  archi- 
tecture to  designate  this  portion  of  the  insect  economy, 
and  perhaps  the  term  can  hardly  be  applied  in  fairness 
to  homes  which  are  mere  tunnels  and  galleries  bored 
in  the  earth  or  in  wood.  But  who  would  deny  it  to 
the  exquisite  pensile  nests  of  the  English  wasps,  or 
those  of  many  a  foreign  relative,  to  the  geometric 
precision  exhibited  within  the  hive  of  the  honey-bee, 
or  to  the  edifices  of  some  ants,  as  will  be  presently 
discovered. 

Among  the  communities  which  combine  their 
operations,  there  are  those  of  which  the  object 
is  simply  the  protection  of  the  individuals  com- 
posing them.  To  these  societies  belong  the  cater- 
pillars of  certain  species  of  moths.  The  homes  formed 
by  these  larvae,  though  they  are  not  elaborate,  are 
interesting  in  several  minute  circumstances.  But  they 
fall  short  in  every  respect  of  the  attractive  nests 
fabricated  by  companies  of  insects  in  their  perfect 
state,  in  view  not  only  of  self-preservation,  but  of  the 
nurture  and  education  of  their  young  as  well. 

Of  these  the  nests  of  different  kinds  of  ants  are  the 
most  simple  in  their  character.  None  the  less  on  this 
account  they  are  worthy  of  investigation,  owing  to 
dissimilarity  of  design  both  in  outward  form  and 
internal  plan,  on  account  of  the  materials  composing 
them,  and  the  manner  that  they  answer  the  wants  of 
the  species.  Their  size  is  astonishing,  and  outrivalled 
only  in  the  inferior  departments  of  the  animal  kingdom 
by  the  works  of  the  coral  animalcula.  They  may  be 
formed  with  earth,  and  consist  either  of  excavation 
underground,  or  of  excavation  combined  with  building 


120          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

on  the  surface.  Their  makers  may  be  called  masons. 
Ants  are  likewise  carpenters  by  trade,  hewing  their 
homes  out  of  solid  tree  trunks  and  roots  often  with  an 
excessively  involved  and  delicate  art.  A  third  kind  of 
nest  is  pensile,  and  composed  of  leaves,  or  of  collections 
of  vegetable  or  animal  matters.  These  three  general 
types  include  many  most  interesting  modifications, 
each  species  of  workmen  being  endowed  with  the 
operative  talent  that  suits  them  best. 

The  common  Wood  Ant,  otherwise  named  the  Hill, 
or  the  Horse,  or  the  Red  (Formica  mfa*\  is  a  good 
representative  of  the  group  (Formicites*)  to  which 
appertain  the  true  ants.  Few  people  in  this  country,  and 
throughout  all  central  Europe,  are  unacquainted  with 
the  dwellings  (see  Fig.  15).  They  consist  exteriorly 
of  elevated  hillocks  or  mounds,  many  of  them  of  large 
dimensions,  made  up  of  bits  of  straw,  wood,  little 
stones,  morsels  of  earth,  leaves,  grain,  in  a  word,  of 
anything  portable  and  within  reach.  Usually  they  are 
situated  in  woods  or  their  neighbourhood  where  the 
undergrowth  is  not  too  dense,  often  under  some  shelter 
such  as  a  bush  or  tree.  They  are  especially  plentiful 
in  fir-woods,  where  the  fallen  needle-like  leaves  of  the 
firs  afford  abundance  of  building  material  ready  to 
hand.  At  the  first  glance  the  dome  seems  nothing 
but  a  rude  confused  mass  ;  in  reality  its  internal  con- 
struction presents  an  arrangement  that  is  excellently 
adapted  to  promote  the  welfare  and  comfort  of  the 
inhabitants,  ensuring  them  free  liberty  of  action 
throughout,  and  protection  at  once  from  extremes  of 
heat  and  cold  by  the  maintenance  of  a  genial  warmth. 
It  is  composed  of  numberless  small  chambers,  united 


tv 


SOCIAL  HOMES 


121 


together  by  galleries,  in  order  a  series  of  flats  or 
storeys  ;  besides  these  there  are  more  or  less  irregular 
avenues  communicating  with  the  outside.  In  fact, 


FIG.  15. — Section  through  a  typical  nest  of  Formica;  after  Smith. 

the  fragments,  instead  of  being  thrown  down  confusedly 
and  without  purpose,  are  carefully  disposed  after  a  defi- 
nite though  not  very  regular  plan.  The  beams  are  piled 


122          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

ingeniously,  and  their  interstices  in  some  parts  of  the 
nest  are  filled  up  with  earth,  grains,  and  scraps  of  dried 
leaf,  giving  strength  and  solidity  to  the  whole  mount. 
It  is  worthy  of  note  that  the  longest  sticks  are  reserved 
for  the  galleries,  in  order  to  prevent  by  every  possible 
means  the  materials  from  falling  in,  and  causing  in- 
terruption in  the  routes  of  communication.  Due  to 
this  orderly  method  of  erection  the  domes  can  with- 
stand the  shocks  both  of  rain  and  wind,  without  being 
penetrated  by  the  one  or  blown  away  by  the  other 
The  nest  is  completed  by  a  corresponding  labyrinth  of 
chambers  and  galleries  in  the  ground,  from  which 
mining  system  the  earth  granules  utilized  in  the  upper 
fabric  are  obtained. 

To  all  appearances  the  entrances  to  the  galleries 
from  the  outside  are  exceedingly  ill-fitted  for  the  ex- 
clusion of  damp  and  of  nocturnal  intruders  on  the 
ants'  privacy.  The  openings  exist  at  the  owners' 
pleasure.  In  the  early  morning  they  are  nowhere 
visible,  and  the  nest  is  as  though  deserted  ;  or  a  few 
small  cracks  are  apparent,  whence  issue  forth  some 
workers  betimes.  By-and-by,  as  the  day  advances 
the  passages  are  swept  and  cleared,  and  the  holes  are 
made  for  the  day,  while  the  entire  population  become 
actively  engaged  in  their  several  avocations.  Only  if 
the  day  be  fine  however.  Should  it  rain  the  portals 
are  kept  fast,  or  if  the  sky  be  cloudy  they  are  partially 
opened.  The  drawing  in  of  night  sees  them  wholly 
closed,  when  all  the  inmates  gradually  retire  to  the 
interior  to  enjoy  rest  from  labour,  confident  of  peace, 
a  few  sentinels  being  left  to  guard  the  gates.  Should 
a  brilliant  morning  and  consequent  wide-flung  doors 


IV  SOCIAL  HOMES  123 

be  succeeded  by  heavy  showers,  the  ants  hasten  to 
prevent  catastrophe  by  the  re-establishment  of  the 
barriers,  and  every  member  appears  willingly  to  give 
its  quota  of  help  to  speedily  accomplish  the  work  in 
hand. 

The  formation  of  a  nest  may  be  traced  from  the 
beginning  by  brief  close  investigation  into  the  state  of 
society  of  a  large  community  during  the  early  months 
of  summer.  Here,  in  addition  to  the  presence  of  the 
vast  multitude  of  wingless  worker  ants,  and  some 
females  now  in  like  condition,  a  certain  number  of 
young  winged  males  and  females  are  all  ready  and 
eager  to  escape  from  home.  Soon  after  their  birth, 
taking  advantage  of  a  favourable  opportunity,  usually 
on  some  warm  still  afternoon,  they  adventure  out. 
Some  of  the  females,  or  so-called  '  queens,'  are  com- 
pelled to  return,  and  having  torn  off  their  wings 
which  are  no  longer  of  use,  with  the  assistance  of  the 
workers,  they  settle  down  to  an  unintermitting  seden- 
tary existence,  replenishing  the  population  of  the  only 
abode  they  will  ever  know.  Other  females  while  in 
this  comparatively  helpless  condition  are  conveyed  by 
workers  to  new  situations,  where  they  become  the 
founders  of  new  colonies. 

In  effecting  the  establishment  of  a  colony,  the  little 
company  at  first  betake  themselves  to  mining.  With 
their  mandibles  they  set  arduously  to  work,  until 
by  dint  of  prolonged  and  strenuous  labour  a  cavity  in 
the  earth  is  formed.  Meanwhile  some  of  the  future 
inhabitants  of  the  nest  may  be  seen  wandering  about 
the  vicinity  in  search  of  building-stuffs  for  the 
exterior.  Scrap  after  scrap  is  gathered,  and  laid  over 


124          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

the  entrance  to  the  hole,  one  piece  being  crossed  over 
the  other,  while  the  lowermost  bits  are  stuck  into  the 
earth  so  as  to  fix  the  foundations  of  the  aerial  erection. 
Many  of  the  little  creatures  are  equally  busy  in  ming- 
ling the  vegetable  morsels  constantly  brought  in  by 
their  fellows,  with  the  grains  of  earth  thrown  up  in 
hollowing  the  underground  apartments,  tempering  the 
granules  with  rain  water,  which  harden  in  the  sun  and 
effectually  bind  together  the  different  substances. 
Thus  do  these  fragile  materials,  without  cement  and 
not  even  interwoven,  constitute  a  tolerably  firm  com- 
position, one  able  to  withstand  the  weather,  and  the 
bustling  energy  of  the  ants  in  their  life's  occupations. 
Day  by  day  the  stories  composed  of  chambers, 
cells,  large  and  small,  and  passages,  are  superimposed 
upon  one  another,  and  the  edifice  increases  in  size, 
cavities  being  left  open  throughout  the  day  as  the 
work  proceeds,  where  the  builders  intend  to  construct 
the  galleries  which  are  to  lead  to  the  interior. 

During  the  first  fine  days  of  the  year  the  eggs  begin 
to  be  laid,  and  from  this  moment  until  as  perfect 
insects  they  are  fully  competent  to  '  do  '  for  themselves, 
the  young  become  the  objects  of  tenderest  solicitude 
to  the  nursing  ants.  Placed  alternately  in  the  recesses 
and  the  outer  chambers  of  the  nest, — in  the  first  at 
night  for  warmth,  whence  in  the  morning  they  are 
removed  to  the  upper  rooms  where  the  sun's  heat 
penetrates,  so  as  to  be  maintained  at  a  uniform  temper- 
ature,— gradually  under  this  fostering  care  the  eggs 
increase  in  bulk,  and  the  larvae  are  hatched.  Now  even 
more  than  formerly,  the  little  ones  demand  attention. 
In  addition  to  change  of  room  every  morning  and 


IN- 


SOCIAL  HOMES 


night,  and  frequently  at  shorter  intervals,  in  conse- 
quence of  sudden  alteration  in  weather,  as  an  unlocked 
for  shower,  which  will  cause  the  workers  to  hurry  their 
charges  away  from  the  surface  to  the  inner  depths,  or 
should  the  sun  become  too  hot  in  the  day  cells, — the 
rapidly  developing  nurslings  have  to  be  vigilantly 
cleansed  and  fed,  When  full  grown  the  majority  of 
ant-larvae  spin  silken  cocoons  around  them.  In  this 
state  they  are  well  known,  and  collected  as  food  for 
young  pheasants.  Popularly  they  are  termed  ants' 


FIG.  16. — Section  through  the  nest  of  the  Leaf-cutting  Ant  CEcodoina  ccphalotcs 
from  Belt. 

eggs,  but  how  the  egg  could  exceed  the  size  of  the 
insect  that  laid  it  is  a  problem  that  never  seems  to 
suggest  itself  to  the  nomenclators.  The  pupae,  like  the 
larvae  before  them,  are  carried  by  the  workers  from 
room  to  room,  and  for  the  same  purpose.  Eventually 
their  metamorphoses  are  almost  complete,  still  the 
nurses  do  not  dare  to  relax  their  attendance  upon  them. 
Without  assistance  the  immature  ant  is  incapable  of 
freeing  itself  from  its  covering,  and  would  perish 
miserably,  ere  it  can  be  said  to  have  really  lived.  The 
workers,  observant  of  the  right  moment,  tear  open  the 


126          ROMANCE  OF  THE  INSECT  WORLD.      CHAP. 

cocoon  with  their  mandibles,  and  set  free  the  now 
perfect  creature.  For  a  little  while  it  is  weakly,  and 
unable  to  take  care  of  itself,  and  assume  its  share  of 
the  tasks  of  the  hive.  So  long  as  feebleness  continues 
the  nurses  never  lose  sight  of  their  tender  dependant, 
they  watch  it  until  strength  and  knowledge  of  its 
duties  are  acquired.  The  affectionate  workers  even 
accompany  their  young  winged  nurslings  to  the  surface 
of  the  dome,  and  feed  them  for  the  last  time  before 
they  start,  in  turn,  on  their  nuptial  flight. 

On  the  occasion  of  this  swarming,  which  has  been 
already  alluded  to,  it  was  formerly  thought  that  when 
any  female  alighted  at  a  great  distance  from  the  nest, 
driven  thither  by  the  wind,  or  carried  merely  by 
flight,  she  found  her  way  back  to  her  original  quarters. 
This  has  been  proved  to  be  impossible.  On  the  con- 
trary, a  solitary  female  falling  to  the  ground  in  an  out- 
of-the-way  spot,  has  been  observed  to  creep  into  a 
hole,  and  to  cast  aside  her  wings,  and  with  them  her 
dignity,  as  it  were,  and  usual  exemption  from  toil, 
taking  upon  herself  unaccustomed  menial  offices. 
Alone,  unaided,  she  constructs  a  small  nest,  and  lays 
some  eggs,  and  feeds  the  young,  and  rears  them  to 
maturity.  Wonderful  to  say,  she  appears  to  be  aware 
of  the  necessity  of  developing  them  into  workers.  No 
sooner  do  they  attain  perfection  and  the  capacity  to 
assume  adult  labour,  than  the  mother  relinquishes  the 
duties  foreign  to  her  nature,  and  falls  back  on  the  sole 
occupation  of  egg-laying ;  leaving  her  progeny  to 
enlarge  the  dimensions  of  the  dwelling,  to  keep  it  in 
repair,  to  defend  it,  to  provision  themselves  and  her 
with  food,  and  to  act  the  part  of  nurses  to  the  young, 


SOCIAL  HOMES 


127 


with  which  she  continues  to  stock  the  colony.  Subse- 
quently these  include  among  them  winged  males  and 
females. 

The  wood  ant  is  singular  in  having  preference  for  an 
open-air  life  during  the  heat  of  the  day,  and  is  con- 
tinually on  the  outside,  seeking  for  food  or  employed 
on  the  exterior  of  the  dome  until  darkness 
compels  it  to  desist.  It  is  seemingly  fearless  of 
being  surprised  by  enemies,  at  least  during  the 


FIG.  17. — Saiiba  or  Leaf-cutting  Ant  carrying  leaf  ;  from  Bates. 

day,  and  does  not  construct  a  long  covert  way  to  its 
nest,  as  if  for  concealment,  like  the  yellow  and  brown 
kinds.  But  the  wood  ant  never  fails  in  its  precaution 
against  attack  and  assault  of  the  dwelling  by  night, 
and  when  business  must  be  completed  after  dusk,  it  is 
done  with  shut  doors.  The  actual  manner  of  obliterat- 
ing the  apertures  is  noteworthy.  To  the  entrance  of 
the  avenue  which  the  ants  desire  to  close,  beams  are 
brought  forward  and  deposited  in  the  stubble ;  similar 


128          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

morsels  arc  placed  above  but  in  another  direction, 
and  pieces  smaller  as  the  work  proceeds.  At  length 
bits  of  dried  leaves  and  other  materials  of  larger  size 
are  laid  down  ;  the  exact  art  in  miniature  of  car- 
penters when  roofing  a  house.  Nature  seems  every- 
where in  advance  of  those  inventions  of  which  we  as 
men  are  so  proud.  Doubtless  had  careful  observers  of 
these  things  existed  in  early  times,  many  mechanical 
devices  which  have  taken  civilised  nations  centuries  to 
discover  and  to  perfect,  would  have  played  their  part 
in  the  world's  history  considerably  sooner  than  they 
have  done  in  fact. 

The  nests  of  F.  rufa  are  particularly  large  in  the 
fir- woods  of  Scotland,  where  I  have  seen  them  the 
size  of  small  haycocks,  and  occupied  by  absolutely 
countless  numbers.  Yet  these  are  mere  molehills  as 
compared  with  the  enormous  mounds  of  species,  ap- 
parently of  the  same  family,  in  warmer  climates. 
Stedman  speaks  of  ant-hills  in  Surinam  over  six  feet 
high  and  at  least  a  hundred  feet  in  circumference  ; 
Malouet  mentions  having  come  across  specimens  in 
the  forests  of  Guiana  of  a  height  that  he  computes  at 
fifteen  or  twenty  feet,  with  a  diameter  at  the  base  of 
from  thirty  to  forty. 

Although  the  architecture  of  most  ants  is  possessed 
of  strong  points  of  resemblance,  each  species  chooses 
a  particular  position  for  its  nest  and  establishes  it  on 
its  own  plan.  Like  F.  rufa,  many  that  work  in  earth 
are  admirable  subterranean  burrowers.  Perhaps  the 
brown,  F.  brunnea,  carries  off  the  palm,  a  species  not 
very  common  in  this  country.  Though  one  of  the 
smallest,  it  is  remarkable  for  ingenuity  and  the  beauty 


iv  SOCIAL  HOMES  129 

of  its  finished  workmanship.  The  nest  consists  of 
series  of  stories,  sometimes  not  fewer  than  forty, 
twenty  below  the  level  of  the  soil  and  as  many  above, 
which  last  are  not  horizontal,  they  follow  the  slope  of 
the  ant-hill,  and  lie  one  upon  the  other  to  the  ground 
floor,  presenting  the  appearance  exteriorly  of  an 
elevated  dome-shaped  mound.  Each  story,  separately 
considered,  is  composed  of  cavities,  narrow  chambers, 
and  long  galleries  which  preserve  communication 
between  both.  All  are  smoothed  as  though  with  a 
plasterer's  trowel,  and  are  about  the  fifth  of  an  inch 
high.  While  some  of  the  more  spacious  rooms  have 
only  one  entrance  from  above,  or  in  addition  a  second 
leading  to  the  story  lower,  some  are  large  open  spaces, 
being  in  fact  the  points  where  meet  several  of  the 
main  galleries,  a  kind  of  cross  roads,  and  are  connect- 
ed with  subterranean  passages  frequently  carried  to  a 
distance  of  several  feet  from  the  hill.  The  arched 
roofs  of  the  chambers,  which  are  often  more  than 
two  inches  across,  are  supported  by  excessively  slen- 
der partition  walls,  or  by  small  pillars  and  true  but- 
tresses. The  building  material  consists  of  soft  clay 
excavated  from  the  bottom  in  mining,  and  is  often 
moist  enough,  since  the  sun  cannot  penetrate  to  the 
lower  depths.  Were  the  supply  taken  from  the 
surface,  business  would  be  practically  at  a  standstill 
during  dry  weather. 

To  enable  him  to  watch  these  ants,  Huber  had  a 
carefully  arranged  contrivance  constructed,  a  sort  of 
vivarium,  where  the  insects  were  furnished  with  the 
conveniences  to  prosecute  their  ordinary  work.  While 
some  might  have  been  seen  busily  engaged  upon  the 

K 


130          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

soil,  kneading  and  moulding  it  with  their  mandibles 
into  ductile  pellets,  an  action  analogous  to  brick- 
making,  others  were  as  diligently  scooping  out 
shallow  cavities  in  the  clay  floor,  the  ridges  that  were 
left  being  the  foundations  of  the  future  walls.  On 
these  pellet  after  pellet  prepared  for  use  were  adjusted, 
and  spread  firmly  and  evenly,  greater  compactness 
being  obtained  by  light  pressure  of  the  ants'  fore-feet. 
However  numerous  the  masses  may  be,  the  walls  when 
finished  look  uniform  and  unbroken.  Openings  are 
made  where  necessary  in  the  masonry  to  admit  of 
communication,  and  when  the  two  walls  of  any  gallery 
or  chamber  reach  the  proper  height  the  space  between 
them  is  covered  in  by  the  ceiling.  The  method  of 
construction  is  to  mould  pellets  into  each  angle  of  the 
apartment,  and  also  to  the  top  of  the  pillars,  extending 
the  roof  by  successive  layers  of  pellets,  as  fast  as  one 
row  becomes  dry  a  second  being  added  until  the 
approaching  sides  meet. 

No  glutinous  matter  is  introduced  into  the  masses 
of  clay  by  way  of  mortar  or  size  for  consolidating  or 
strengthening  the  building.  The  particles  adhere 
merely  by  juxtaposition,  the  peculiar  kneading  and 
biting  to  which  they  are  subjected  rendering  them  very 
tenacious.  Moisture,  however,  is  absolutely  necessary 
to  the  ants,  and  if  deprived  of  it  in  the  shape  of  gentle 
showers,  or  if  the  clay  from  below  is  not  properly 
damp  of  itself,  they  abandon  their  labour  as  hopeless 
and  wait  patiently  for  rain.  In  the  event  of  the  con- 
tinuance of  dry  weather,  they  pull  down  again  the 
crumbling  apartments  that  are  not  covered  in.  As 
regards  the  ants  kept  by  Huber  in  captivity,  he  found 


IV 


SOCIAL  HOMES 


that  whenever  they  ceased  to  build  he  could  almost 
always  induce  them  to  resume  by  dipping  a  brush  in 
water,  and  striking  it  with  the  hand,  so  that  the 
fluid  fell  like  fine  rain.  As  soon  as  they  felt  the 
refreshing  drops  they  would  immediately  regain  their 
activity.  Much  wet  is  as  inconvenient  to  them  as  a 
drought.  But  when  their  walls  are  complete  they 
are  very  strong,  and  extremes  of  heat  and  moisture 
appear  only  to  increase  the  cohesion.  These  insects 


FIG.  18. — Agricultural  Ant  of  Texas  (Pogonoinyrmcx  barbatiis).     Large  flat  circular 
disk  and  open  roads  made  above  the  subterranean  formicary;  from  McCook. 

avoid  the  sun,  and  seem  to  work  chiefly  at  night  and 
during  light  misty  rain.  Wonderfully  assiduous,  they 
have  been  known  to  construct  a  story,  with  all  its 
saloons,  vaulted  roofs,  partitions,  and  galleries,  in  from 
seven  to  eight  hours. 

Two  other  masons  common  over  a  great  part  of 
Europe,  the  ash-coloured  or  dusky  F.  fusca  *  and  the 
so-called  mining  ant,  F.  cunicularia,  form  similar 
nests,  but  the  last-mentioned  makes  no  dome.  Both 

K  2 


132          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 


are  probably  less  particular  in  the  selection  of  their 
building  materials  than  F.  brunnea.     The  hillock  of 

the  ash-coloured  ant  always 
presents  thick  walls,  the  stories 
are  well  marked,  the  chambers 
large  with  vaulted  ceilings,  and 
the  galleries  strictly  speaking 
are  large  oval  passages.  The 
chambers  and  galleries  rest 
upon  a  solid  basis,  arising  from 
the  mode  of  heightening  the 
habitation.  The  existing  roof 
is  covered  with  a  thick  layer 
of  fresh  moist  clay,  converting 
it  into  a  floor  for  the  pro- 
posed story.  On  this  the 
builders  proceed  to  plan  the 
erection  intended,  forming 

FIG.  19. — Agricultural  Ants  cutting  .    .  r     ,  ,     . 

down    obtruding    grass;      from       CaVltlCS  OI  almOSt  CQUal  depth 
McCook.  .    . 

in  it,  and  raising  the  inter- 
vening elevations  into  wall-like  partitions,  having 
first  reduced  the  foundations  to  a  due  thick- 
ness and  removed  the  loose  earth  from  the  floors 
of  the  apartments.  Lastly,  all  is  closed  in.  The 
muscular  power  and  energy  of  these  ants  are 
truly  amazing,  as  exemplified  by  the  observations 
of  Huber,  who  watched  a  single  worker  make 
and  roof  in  a  gallery  two  to  three  inches  long, 
she  herself  fetching,  and  kneading,  and  placing 
her  own  materials,  and  the  interior  was  rendered 
perfectly  concave,  a  day's  work,  in  propor- 
tion to  her  size,  far  beyond  the  power  of  man. 


iv  SOCIAL  HOMES  133 

This      ant      prefers      a     nest-site      with      southern 
aspect. 

The  Saiiba  or  Coushie  ant  (CEcodoma  cepJialotes), 
peculiar  to  tropical  America,  is  a  mason  that  exceeds 
the  European  species  in  the  magnitude  of  its  labours. 
Its  nests,  found  in  plantations  and  woods,  consist  of 
dome-like  edifices  elevated  over  underground  earth- 
works (see  Fig.  16).  The  domes  differ  in  colour  from 
that  of  the  surrounding  superficial  soil,  owing  to  being 
formed  of  earth  brought  up  from  a  considerable  depth. 
Frequently  no  less  than  forty  feet  in  diameter,  with  a 


FIG.  20.— Gravel  cone  nest  of  Honey  Ant  built  partly  round  a  tuft  of  gramma 
grass  ;  from  McCook. 

height  of  two  feet,  measurements  simply  gigantic 
having  regard  to  the  builders,  they  dwarf  into  utter 
insignificance  the  mightiest  efforts  of  man,  the  relative 
dimensions  of  the  workers  being  considered.  But 
though  the  domes  are  immense,  they  arc  as  nothing 
compared  with  the  limits  of  the  underground  galleries, 
which  are  often  of  almost  incredible  extent,  and  show 
no  trace  of  their  presence,  and  suddenly  the  ants  will 
come  to  the  surface  where  least  expected.  So  vast 
are  the  subterranean  passages  and  so  complicated, 


134          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

that  they  have  never  been  thoroughly  investigated,  but 
an  idea  of  their  size  is  obtained  from  the  fact  that  once 
when  sulphur  smoke  was  introduced  into  a  nest  it 
issued  at  an  outlet  seventy  yards  distant.  Mr.  Bates 
relates  that  a  species  has  been  known  to  excavate  a 
tunnel  under  the  bed  of  the  river  Parahyba,  in  Brazil, 
at  a  place  where  it  was  as  broad  as  the  Thames  at 
London  Bridge.  Galleries  radiate  from  the  dome  in 
all  directions ;  the  nest  also  contains  rounded  chambers 
about  as  large  as  a  man's  head.  The  entrances  are 
small  and  numerous  and  generally  closed ;  very  rarely 
the  ants  are  seen  at  work  upon  the  mounds. 

Popularly  known  as  leaf-cutters,  these  ants  arc  a 
veritable  scourge  in  central  and  tropical  America, 
where  they  abound,  and  may  constantly  be  observed 
forming  broad  processionary  columns  on  their  way  to 
and  from  the  scenes  of  the  fearful  havoc  they  commit, 
persistently  and  laboriously  abstracting  quantities  of 
pieces  of  foliage  from  the  trees  as  large  as  sixpenny 
bits.  Valuable  cultivated  plants  suffer  most  from  their 
attacks,  the  orange,  lemon,  coffee,  and  mango  espe- 
cially. In  some  districts  agriculture  has  been  rendered 
almost  impossible  in  consequence,  or  has  been 
abandoned.  Their  mode  of  cutting  off  the  bits  of 
leaves  is  very  interesting.  Equally  attractive  are  the 
insects  when  in  order  of  procession,  returning  home 
laden  with  their  spoil  like  multitudes  of  animated 
leaves,  each  workman  marching  along  holding  its 
portion  in  its  jaws  erect  by  one  of  the  edges.  The 
habit  has  obtained  for  them  the  name  of  Parasol  Ants, 
the  burden  being  supposed  to  be  carried  to  shield  its 
bearer  from  the  sun  (see  Fig.  17).  It  is  now  ascertained 


iv  SOCIAL  HOMES  135 

that  the  gleanings  are  minutely  subdivided  and  stored  in 
the  formic  chambers  until  decayed.  On  the  rotten  mass 
grows  a  minute  white  fungus  on  which  the  ants  feed  ; 
they  are  in  fact  mushroom  growers  and  eaters. 

Great  interest  is  attached  to  certain  mason  ants 
of  the  New  World,  the  so-called  Agricultural 
Ants  of  Texas  and  Florida  and  the  Occident 
Ants  of  the  American  plains.  The  formicaries  of 
Pogonomyrmex  barbatus  are  scattered  over  the  light 


FIG.  21. — View  of  the  nest   of  a   Provident  Ant  (Atta  barbara)  from  Mentone 
showing  a  granary  excavated  in  rock  and  the  conical  refuse  heap. 

soil  on  the  hill  slopes  of  Texas,  in  the  deep  dark  earth 
of  the  highlands  and  valleys,  among  the  rocks,  indeed 
almost  everywhere.  Externally  they  are  for  the  most 
part  flat,  smooth,  circular  disks  in  the  midst  of  sur- 
rounding herbage,  presenting  the  appearance  of  minia- 
ture "  clearings  "  in  the  American  backwoods  (see  Fig. 
1 8)..  Some  of  them  are  as  large  as  from  seven  to  twelve 
feet  in  diameter,  the  average  ones  reach  a  diameter  of 
only  four  or  five  feet,  covering  a  space  of  from  twenty- 


136          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

one  to  thirty-six  square  feet.  From  this  central  plat- 
form, as  it  were,  broad  and  similarly  clean  paths 
or  avenues  branch  off  into  the  encircling  vegeta- 
tion, they  gradually  narrow,  and  almost  imperceptibly 
blend  with  the  vacant  spots  between  tufts  of 
grass.  In  number  these  paths  are  usually  three  or 
four,  sometimes  there  are  as  many  as  seven,  with  a 
width  at  their  entrance  upon  the  disk  frequently  of  two 
and  a  half  to  three  inches,  occasionally  enlarging  to 
five  or  six.  A  hole  within  the  disk  leads  to  the  sub- 
terranean regions,  which  include  store-rooms  for  the 
seed,  nurseries,  and  other  chambers,  their  arrangement 
being  more  or  less  in  stories. 

Extraordinary  must  be  the  labour  on  the  part  of 
these  insects  in  effecting  the  removal  of  the  rank 
vegetation  of  the  country  from  the  bounds  and 
approaches  of  their  nest.  The  weeds  stand  in  a  well- 
nigh  perfect  circle  around  the  circumference  of  the 
cleared  space.  Tufts  of  grass,  wild  sage,  the  daisy, 
and  such-like  sturdy  growths  are  there,  with  stalks  at 
times  as  thick  as  one's  thumb,  and  over  two  feet 
high.  The  plucky  beings  appear  to  bite,  and  saw, 
and  twist,  and  tug  at  the  leaves  and  stems  until  they 
are  severed  and  can  be  borne  away  (see  Fig.  19).  Pre- 
sumably, the  avenues  are  denuded  in  similar  fashion. 
During  the  winter  months,  when  many  of  these  ants 
retire  under  ground,  the  clearings  fall  into  sad  disrepair, 
and  the  weeds  intrude,  to  be  as  vigorously  expelled 
in  the  following  spring,  when  warmth  once  more 
recalls  the  workers  to  set  all  things  in  order.  The 
use  of  the  pavements  is  doubtless  to  facilitate  entrance 
to,  and  exit  from,  the  home,  so  as  to  reduce  the 


iv  SOCIAL  HOMES  137 

fatigue  inseparable  from  toil.  The  avenues  are  made 
with  like  intent,  enabling  speedy  and  ready  journey- 
ing to  the  harvest  grounds  and  back.  The  exertion 
involved  in  searching  for  the  wished-for  plant-seeds, 
in  adjusting  them  for  convenient  carriage,  and  in 
bearing  the  weights,  is  remarkable  considering  the  size 
of  the  workmen  at  their  calling,  and  amply  justifies 
them  in  lightening  their  labours  by  every  means 
in  their  power.  The  seeds  are  stored  in  large 
quantities,  entire  as  gathered,  and  also  stripped  of 
their  shells,  and  are  believed  to  serve  the  gleaners 
as  food  during  their  confinement  in  winter.  Ref- 
use heaps,  consisting  of  the  discarded  shells  and 
glumes,*  are  raised  outside,  and  have  been  facetious- 
ly termed  the  kitchen  middens.  On  opening  some  of 
the  nests  in  spring  the  granaries  are  discovered  to  be 
not  nearly  so  well  stocked  as  in  the  fall,  a  fact  that 
argues  strongly  in  favour  of  the  actual  consumption  of 
the  seed. 

As  the  season  advances,  and  autumn  once  more 
deepens  into  winter,  while  some  disks  continue  to  be 
kept  free  of  herbage  of  every  description,  many  of  the 
platforms  become  partially  covered  with  a  row  of  one 
particular  plant,  the  Aristida  stricta,  or  "Ant  Rice." 
The  circular  cluster  is  strictly  limited  by  the  outer 
bound  or  circumference  of  the  clearing,  beyond  which 
grows  the  ordinary  wild  grass  of  the  locality.  It 
ripens  by  the  ensuing  spring,  and  there  seems  little 
doubt  that  from  it  the  ants  then  gather  in  a  harvest 
of  seed,  subsequently  cutting  down  and  removing  its 
dry  stubble,  along  with  any  weeds  that  have  trespassed 
on  the  private  property  during  winter;  leaving  the 


138          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

"  pavement  "  again  unencumbered  until  autumn,  when 
the  same  favoured  plant  once  more  presents  itself.  It 
has  been  urged  that  the  needle  grass  is  deliberately 
sown  by  the  ants  on  the  cleared  ground  in  summer, 
and  is  cultivated  with  the  intention  of  reaping  a  crop 
from  it  in  the  following  spring.  It  seems  hardly 
possible  to  credit  them  with  such  wisdom.  Nor  on 
the  other  hand,  as  the  opponents  of  this  theory  believe, 
is  it  likely  that  they  are  overtaken  by  the  autumn 
"  rice,"  and  are  unable  to  prevent  it,  since  surely  the 
power  which  enabled  them  to  eradicate  all  usurping 
winter  growth  from  their  domain  in  spring,  would 
admit  of  them  keeping  it  clear.  Besides,  the  exclusive 
occupation  of  the  disk  by  this  grass,  so  long  as  the 
ants  are  up  and  about,  counts  in  favour  of  voluntary 
action  on  the  part  of  the  insects.  Probably  the 
Aristida  is  seeded  yearly  in  a  natural  way  by  drop- 
pings from  the  plant,  or  from  seeds  dropped  or  cast 
forth  by  the  ants  ;  and  the  ants  find  it  to  their  ad- 
vantage to  permit  and  foster  the  ensuing  growth, 
because  of  greater  convenience  of  harvesting  the  seed, 
while,  farmer-like,  they  expel  all  other  vegetation  from 
their  precincts. 

In  some  instances  the  central  clear  space 
is  occupied  by  a  low  mound,  in  shape  some- 
what like  a  volcanic  cone  with  a  crater-like 
depression-  at  the  summit.  A  distinct  flat  bare 
belt  or  zone  may  exist  between  the  mound  and  the 
margin  of  the  nest,  of  no  great  width  ;  or  the  grass  of 
the  surrounding  prairie  may  grow  up  to  the  cone's 
base.  The  material  composing  the  mounds  is  a  light 
sandy  soil.  Other  nests  have  gravel  disks.  Round 


IV 


SOCIAL  HOMES 


139 


the  opening  to  the  underground  apartments  is  a  mass 
of  gravel,  which  may  accumulate  into  a  little  heap, 
and  beyond  extends  the  smoothed  belt  of  ground  with 
circulatory  margin.  Entrance  to  the  interior  is  by 


FIG.  22. — Fragment  taken  from  the  trunk  of  an  oak  inhabited  by  Fuliginous 
Ants  ;  from  Huber. 

one,  two,  or  more  gates  ;  apparently  the  tendency  is 
to  increased  numbers  in  nests  with  cones  and  mounds. 
Immediately  within  the  gate  is  a  vestibule,  smooth, 
and  from  one  to  two  inches  wide,  which,  at  a 
distance  from  the  entrance  of  from  half  an  inch  to 


HO          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

two  and  a  half  inches,  diverges  into  tubular  galleries 
connected  with  the  granaries  and  nurseries.  In 
general  these  rooms  are  circular,  oval,  and  crescent- 
shaped.  The  depth  to  which  they  are  carried  prob- 
ably varies,  but  nests  have  been  excavated  as  far  as 
four  feet  below  the  surface  and  no  termination  of  the 
mining  was  reached.  Rooms  even  at  two  and  a  half 
feet  down  are  packed  with  seed,  and  narrow  gang- 
ways are  left  at  the  outer  margin  between  the  grain- 
heaps  and  the  wall.  The  elevations  upon  the  disks  are 
used  for  habitation,  and  are  not  simple  accumulations 
of  earth  excavated  from  the  underground  cells  and 
galleries.  The  architecture  of  the  Florida  harvester 
(P.  crndelis]  is  in  close  resemblance  to  the  cone 
structures  of  the  Texan  agriculturist. 

The  nests  of  the  other  known  North  American 
congener  of  Pogonomyrmex,  the  Occident  Ant  of 
the  great  American  plains  (P.  occidentalis\  are  similar 
in  exterior  to  the  gravel-covered  cones  of  the  Texas 
and  Florida  harvesters.  They  form  conspicuous 
objects  upon  the  level  plains,  or  gently  sloping  hills, 
alike  by  their  elevation  and  their  great  numbers.  The 
cone  rises  to  a  height  rarely  exceeding  ten  inches, 
though  it  appears  much  more,  owing  partly  to  the 
situation.  It  generally  stands  in  or  near  the  centre  of 
a  round  or  elliptical  pavement  or  clearing,  but  no  crop 
of  "  rice  "  breaks  its  monotony  ;  it  is  always  totally 
freed  of  vegetation,  unless  it  be  for  an  occasional  tuft 
or  blade  of  grass  straggling  here  and  there.  Its  use 
then  differs  from  that  to  which  the  Texan  nest-space 
is  put,  since  it  is  no  harvest-field.  Its  advantages, 
however,  are  manifest.  By  it  the  ants  gain  easy 


IV 


SOCIAL  HOMES 


141 


ingress  and  egress  to  and  from  their  home  when 
pursuing  their  daily  tasks,  obviating  the  toil  unavoid- 
able had  the  way  been  obstructed  by  plants.  Vege- 
tation in  the  immediate  vicinity  of  the  nest  is  likewise 
highly  dangerous,  in  that  it  affords  concealment  to 
enemies  at  close  quarters.  It  may  be  also  that  plants, 
seeing  that  they  harbour  damp,  would  be  injurious  to 


FIG  23. — Pseudomyrma  bicolor  inhabiting  Acacia  comigera. 

the  young ;  and  the  roots  might  penetrate  to  the 
interior  of  the  home  and  cause  damage  and  incon- 
venience. The  well-established  and  ordered  roads 
between  the  formicary  and  the  harvest-grounds,  so 
characteristic  a  feature  of  the  Texas  communities,  are 
absent,  a  fact  that  perhaps  reflects  to  the  credit  of  the 
ants  in  question.  For  while  the  vegetation  surround- 


142          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

ing  the  clearings  of  the  Agricultural  Ant  is  dense,  and 
pathways  through  it  are  an  advantage,  if  not  a 
necessity,  generally  on  the  American  plains  where 
the  Occidents  occur,  the  Gramma  Grass  (Bouteldua 
oligastachyd)  prevails,  which  grows  in  tufts  or  bunches 
separated  from  each  other  by  several  inches,  and  the 
intervening  spaces  present  only  a  smooth  level  soil, 
so  that  specially  made  roads  are  uncalled  for. 

The  cone  is  covered  exteriorly,  roofed  as  it  were 
with  a  coating  of  pebbles  to  the  thickness  of  about 
half  an  inch,  not,  or  but  sparsely,  intermingled  with  the 
soil  below,  which  is  chiefly  the  natural  soil  of  the 
surface,  and  constitutes  the  bulk  of  the  mound.  The 
stones  are  obtained  from  the  subterranean  galleries 
and  chambers,  whence  the  miners  bring  them  up  and 
distribute  them  on  the  top  of  the  cone.  These  objects 
are  of  enormous  weight  as  compared  with  that  of  the 
carriers,  and  their  transportation  from  the  interior 
beds  to  the  outer  atmosphere,  by  way  of  the  sharp 
slopes  or  almost  perpendicular  surfaces  of  the  galleries, 
must  be  a  formidable  task.  The  entrance  or  entrances 
to  the  dwelling,  unlike  those  to  the  cone  nests  of  the 
Agriculturalist,  are  not  in  the  crater-like  depression  on 
the  summit,  but  in  the  side  of  the  cone  and  near  the 
base.  In  width  they  vary  from  about  three-quarters 
of  an  inch  to  three  inches  at  their  mouth,  they  are 
quite  shallow,  simply  penetrating  through  the  gravel 
to  the  inner  soil.  They  open  into  the  vestibule,  and 
from  it  one  or  more  galleries  extend  downwards 
through  the  cone,  and  communicate  with  the  intricate 
system  of  passages,  store-closets,  nurseries,  and  living- 
rooms,  mostly  all  situated  beneath  the  level  of  the 


iv  SOCIAL  HOMES  143 

surface  of  the  ground.  The  Occident  also  shuts  its 
gates  in  the  evening,  and  on  the  occurrence  of  a 
storm  ;  it  re-opens  them  late  in  the  morning.  Its 
labours  it  confines  to  the  daylight  hours. 

In  form  and  plan  the  interior  follows  closely 
that  of  the  Texas  Agriculturalist ;  in  fact  a 
striking  resemblance  in  this  respect  exists  among  all 
these  ants.  The  rooms,  mere  lateral  expansions  of 
the  galleries,  measure  at  most  about  three  and  a  half 
inches  in  width,  their  greatest  length  is  about  five  or 
six  inches.  The  galleries  are  cylindrical,  and  of 
various  lengths,  and  rarely  exceed  a  diameter  of  half 
an  inch.  The  apartments  seldom  extend  beyond  the 
limits  of  the  "  clearing,"  and  chiefly  underlie  the  cone 
itself.  Dr.  McCook  ascertained  that  they  descend  to 
a  depth  of  between  eight  and  nine  feet !  Many  of 
them  are  granaries ;  a  single  room  has  been  found  to 
contain  seed  to  the  amount  of  two  tablespoonfuls. 
These  deposits  seem  to  clearly  prove  the  harvesting 
proclivities  of  the  Occident  Ant,  and  beyond  doubt  the 
harvest  is  reaped  for  food.  Dr.  McCook,  when  engaged 
inexaminingthese  formicaries,  came  upon  rooms  packed 
full  of  gravel,  a  circumstance  attributed  by  him  to  a 
division  of  labour  among  the  ants  in  their  herculean 
mining.  He  conjectures  that  it  is  here  the  pebbles 
are  carried  by  those  labourers  who  cut  them  away  from 
the  soil  in  which  they  are  embedded,  when  making 
the  deep  chambers  ;  while  a  second  gang  thence  trans- 
ports them  to  the  upper  regions,  and  arranges  them 
upon  the  cone.  Some,  however,  Dr.  McCook  says, 
were  not  simple  dumping-rooms  to  prevent  stagnation 
of  work,  but  veritable  lumber-rooms,  emmetonian 


144          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

garrets,  for  they  had  evidently  contained  the  gravel 
for  a  length  of  time,  and  were  apparently  sealed  up  in 
the  very  midst  of  the  nest. 

The  nests  of  the  honey-storing  ants  of  Mexico  like- 
wise consist  externally  of  gravel-covered  cone-shaped 
mounds,  of  diminutive  proportions,  attaining  a  height 
seldom  more  than  about  three  inches  (see  Fig.  20).  A 
single  narrow  tubular  entrance-way  descends  through 
the  mound  and  the  earth  more  or  less  perpendicularly,  to 
a  distance  varying  from  three  and  a  half  to  six  inches, 
and  opens  into  the  underground  rooms  and  galleries. 
Arranged  in  several  horizontal  series  one  above  the 
other,  and  intercommunicating  by  vertical  passages, 
these  extend  chiefly  in  one  direction  from  the  gate. 
This  ant  is  nocturnal  in  its  habit  of  foraging  for  food, 
but  does  not  bar  its  door  in  the  daytime,  the  plan 
adopted  by  a  night-wandering  ant  of  Texas  (the  Cut- 
ting Ant,  Atta  fervens).  The  Honey  Ant,  however, 
does  not  neglect  measures  for  safety ;  just  within  the 
margin  of  the  opening  cordons  of  sentinels  are  stationed 
continually,  whose  business  is  to  keep  a  sharp  look 
out  for  enemies,  and  they  appear  to  hold  themselves 
in  readiness  during  storms  to  repair  damage  or  dis- 
arrangement of  the  pebbled  roof.  Disaster  from  this 
cause  is  slight,  owing  probably  to  the  admirable  choice 
of  the  situation  for  the  nest.  The  honey-rooms,  the 
abodes  of  the  inflated  honey-bearing  individuals,  are 
oval,  conspicuously  large,  and  vaulted,  and  will  some- 
times rise  from  a  height  of  barely  three  quarters  of  an 
inch  at  the  walls  to  an  inch  and  a  half  in  the  centre. 
The  galleries  are  smoothed  throughout ;  but  while  the 
floors  and  walls  of  the  honey-rooms  are  pressed  well- 


IV 


SOCIAL  HOMES 


nigh  invariably,  their  ceilings  present  uneven  surfaces, 
being  in  fact  the  natural  condition  of  the  soil  after  the 
sandy  pellets  and  pebbles  have  been  abstracted  by  the 
workers.  The  evenly-spread  earth  is  adapted  for 
gangways  ;  the  roughness  of  the  ceilings  enables  the 
honey-bearers  to  cling  to  them  as  to  a  perch. 


£  FIG.  24. — Nest  of  a  Tree  Ant  ((EcoJ>hylla  smaragdina)  from  India.  ^ 

In  the  homes  of  the  Harvesting  Ants  of  Europe 
(Atta  structor  and  barbard]  elevations  above  the  soil 
are  wanting.  The  large  mounds  frequently  seen  at 
the  entrances  are  rubbish-heaps,  the  kitchen-middens 
of  the  establishments  (see  Fig.  21).  Earth  pellets  and 
grains  of  gravel  brought  out  in  forming  the  subter- 

L 


146          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

ranean  galleries  occur  in  the  heaps  ;  but  they  are  com- 
posed principally  of  plant-refuse,  such  as  the  discarded 
envelopes  of  seed  and  grain,  the  chaff  of  grasses  and 
the  like,  of  which  it  is  advantageous  to  get  rid, 
in  order  to  obtain  greater  space  for  the  storage  of  the 
good  food.  The  workers  relegated  to  the  duties  of 
sorting  the  supplies,  and  casting  forth  those  portions 
that  they  find  to  be  useless,  must  labour  with  assiduous 
energy,  judging  by  the  speedy  rise  of  the  middens  in 
the  harvest  season  ;  and  where  their  position  is 
sheltered  from  wind  and  rain,  they  often  acquire 
considerable  dimensions.  On  and  about  these  ac- 
cumulations, plants  foreign  to  the  immediate  vicinity 
sometimes  flourish,  having  grown  from  seeds  accident- 
ally dropped  by  the  ants  on  their  way  home  from 
the  harvest  grounds.  The  texture  of  the  floors  of 
the  storechambers  usually  differs  markedly  from  the 
surrounding  soil.  The  horizontal  rooms  at  times  lie 
at  great  distances  apart,  but  where  the  soil  is  shallow 
the  galleries  and  granaries  may  be  much  crowded 
together. 

Some  ants  live  in  trees,  and  cut  and  chisel  the  wood 
in  a  wonderful  manner.  The  best  known  is  F.fuligin- 
osa*  the  emmet  or  jet  ant,  a  brilliant  black  insect 
with  pale  reddish  tarsi.*  Its  residences  it  constructs 
in  the  interior  of  old  oaks  and  willows,  gnawing  the 
trunks  into  numberless  stories  always  more  or  less 
horizontal,  with  a  distance  of  about  five  or  six  lines 
between  the  ceilings  and  floors.  The  divisions  are 
scarcely  thicker  than  paper,  a  delicacy  that  is  also 
attained  in  the  vertical  supports  that  apportion  off  the 
separate  chambers.  Communication  in  each  story  is 


riv  SOCIAL  HOMES  147 

by  small  oval  apertures.  In  some  cases  the  walls  are 
reduced  each  into  two  pillars,  rendering  the  apertures 
larger  and  rounder.  When  the  work  is  still  more 
advanced  the  holes  become  square,  and  the  pillars 
originally  arched  at  both  ends  are  hewn  into  straight 
regular  columns,  giving  a  palatial  aspect  to  the  excava- 
tion. Further  progress  transforms  these  partitions 
into  light  cylindrical  columns  possessed  of  a  base  and 
capital  which  are  arranged  in  colonnades,  leaving  a 
free  communication  throughout  the  whole  extent.  The 
rooms  on  or  about  the  same  plane  when  complete 
necessarily  form  a  storey,  but  since  they  are  hollowed 
out  separately,  though  on  similar  plan,  and  the  sides 
are  chiselled  away  as  time  goes  on,  saving  material 
sufficient  to  sustain  the  ceilings,  the  flooring  cannot 
possibly  be  very  level.  This  seems  a  boon  rather 
than  a  disadvantage,  for  the  irregularities  appear 
to  answer  as  cradles  for  the  larvae.  In  roots 
sometimes,  as  in  Australia,  the  nests  look  like 
charming  net-work.  The  material  carved  be- 
comes black,  as  if  smoked,  due  to  exposure  of 
the  wood  to  the  atmosphere,  to  some  emanation 
from  the  ants,  or  to  the  action  of  formic  acid  (see 
Fig.  22). 

Wood-carving  ants  also  infest  the  beams  of  houses, 
and  imperil  their  safety. 

Two  other  tribes  of  Carpenters,  F.  cethiops  and  F. 
flava>  the  yellow  ant,  have  the  ingenuity  to  utilise 
the  saw-dust  that  they  chisel  away.  The  former 
applies  it  to  stopping  up  chinks  and  to  the 
building  of  walls  ;  the  latter,  more  skilled  and  in- 
ventive, composes  entire  stories  of  it  stiffened  and 

L  2 


148          ROMANCE  OF  THE  INSECT  WORLD      CHAP.- 

cemented    into    a    kind    of  papier-mdcht  with    earth 
and  spiders'  web. 

Curious  Carpenter  Ants  (Pseudomyrma  bicolor], 
if  so  they  may  be  termed,  inhabit  the  strong 
curved  spines  of  the  Bull's  Horn  Thorn,  a 
species  of  acacia,  so  called  because  the  branches 
and  trunk  are  covered  with  spines,  set  in  pairs, 
which  bear  great  resemblance  to  the  horns  of 
that  quadruped.  When  the  thorns  are  first 
developed,  and  are  ready  for  tenancy,  they  are 
soft  and  filled  with  a  sweetish  pulpy  substance.  It 
the  ants  eat  away,  preserving  the  hollow  hardened 
shell,  within  which  they  live  and  rear  their  young. 
Near  the  tip  of  the  thorn  an  aperture  is  made  for  en- 
trance and  exit.  Additional  doorways  are  not  required, 
the  partition  separating  the  two  thorns  is  burrowed 
through,  so  that  one  opening  serves  for  both  (see 
Fig.  23).  The  acacia  does  something  more  for  the  ants 
than  provide  them  with  lodging  and  a  stock  of  food 
with  which  to  commence  to  keep  house.  Its  leaves 
are  bi-pinnate,*  and  at  the  base  of  each  two  leaflets 
on  the  mid- rib  a  crater-like  gland  when  the  leaves  are 
young  secretes  a  drop  of  a  honey-like  liquid  of  which 
the  ants  are  extremely  fond,  and  they  constantly  run 
from  one  luscious  mass  to  the  other,  sipping  greedily. 
Nor  is  this  all, — the  tree  likewise  provisions  its  guests 
with  solid  food  in  the  shape  of  yellow  fruit-like 
bodies,  one  at  the  end  of  each  of  the  small  divisions 
of  the  compound  leaflets.  Examined  through  the 
microscope  they  look  like  little  golden  pears.  When 
the  leaf  unfolds  the  fruits  are  not  quite  ripe,  and  the 
ants  are  continually  watching  and  investigating  their 


iv  SOCIAL  HOMES  H9 

progress.  Finding  one  sufficiently  advanced  they 
bite  through  its  small  point  of  attachment  with  the 
pinnule,*  and,  bending  it  down,  break  it  and  bear  it 
off  to  the  nest.  Like  the  glands  the  fruits  do  not 
ripen  at  once,  but  successively,  keeping  the  ants  in 
protracted  attendance  upon  the  new  leaves. 

In  this  way  the  formic  visitors  are  brought  to  act 
as  the  standing  army  of  the  acacia,  at  the  season  of 
the  year  when  it  is  fresh  and  sweet  and  most  liable 
to  attack,  in  return  for  all  the  comforts  and 
luxuries  that  it  bountifully  affords.  Provided  with 
severe  stings  the  protectors  preserve  the  leaves  from 
the  browsing  of  mammalia,  and  from  the  ravages  of 
much  more  dangerous  enemies,  the  leaf-cutting  ants  ; 
nor  can  a  caterpillar  venture  to  approach  without 
suffering  from  the  weapons  of  the  plant's  body-guard. 
Even  should  the  aggressor  be  man,  and  if  he  touches 
or  shakes  a  branch,  they  swarm  out,  making  free  use 
of  their  jaws  and  sting.  To  all  appearances  they 
lead  the  happiest  of  existences.  They  fear  no 
foe,  they  have  ample  food,  and  accommodation  all 
that  heart  could  desire.  But  there  is  a  reverse  side 
to  this  happy  picture.  In  the  dry  season  on  the 
plains  the  acacias  cease  to  grow,  no  young  leaves  are 
produced,  and  the  glands,  now  old,  secrete  no  delicious 
honey.  Then  the  ants  perish  miserably  from  want 
and  hunger,  and  many  of  the  thorns  become 
depopulated.  Again,  when  the  rains  set  in,  the  buds 
burst  forth  with  all  their  dainties  to  the  ant  palate, 
and  accordingly  once  more  the  creatures  multiply. 

Both  in  Brazil  and  Nicaragua  the  flower-buds  and 
young  leaves  of  numerous  plants  are  exempt  from  the 


ISO          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

destruction  of  herbivorous  insects  and  mammals 
through  the  presence  of  their  honey  glands,  whose 
primary  object  is  to  attract  the  guardian  ants.  Among 
others  many  epiphytal*  orchids  and  species  of  Passi- 
flora  may  be  mentioned,  but  they  provide  no  house- 
room  for  their  warders.  On  the  other  hand  the 
Cecropia*  or  Trumpet  Tree  of  Central  America, 
equips  ants  with  a  house,  but  no  food.  The  absent 
necessary  the  tenants  furnish  themselves  with  by 
means  of  Coccidcz,  or  scale  insects,  which  they  intro- 
duce into  their  home,  and  keep  in  their  cells  within 
the  tree.  From  these  lodgers  a  sweet  liquor  is  ob- 
tained, and  the  Cocci  in  turn  find  their  nourishment 
in  the  plant's  juices.  The  stem  of  the  Trumpet  Tree 
is  hollow,  and  divided  into  cells  by  partitions 
which  extend  across  the  interior  of  the  trunk.  The 
ants  gain  admission  by  boring  a  hole  from  the  out- 
side ;  subsequently  they  pierce  the  partitions  and  get 
the  run  of  a  large  space.  In  her  own  royal  cell  the 
queen  of  the  community  resides,  surrounded  by  a 
special  bevy  of  Cocci,  who  yield  her  the  requisite 
sustenance.  The  eggs,  the  grubs,  and  the  pupae, 
have  likewise  their  private  apartments.  In  some 
of  the  Melastomce  ants  occupy  the  pouches 
on  the  petioles*  at  the  bases  of  the  laminae. 
As  in  the  previous  instance,  Coccidce  are  taken 
for  the  supply  of  food.  The  hosts,  on  their 
part,  guard  the  leaves  in  return  for  shelter,  and 
shield  their  attendant  Coccidcz  from  the  attacks 
of  other  animal  forms  in  the  common  habitation. 

Unfortunately   many    of    the     exotic     ants    have 
been  only  slightly  studied  in  respect  of  their  habits, 


iv  SOCIAL  HOMES  151 

and  their  remarkable  architecture  has  been  allowed 
to  pass  without  the  investigation  that  it  merits. 
Among  kinds  neglected  must  be  included  species  of 
Crematogaster.  When  these  run  about  they  hold 
their  abdomen  high  in  the  air,  so  that  it  curves 
backwards  and  overhangs  the  thorax,  whence  is 
derived  their  title  signifying  "hanging-belly."  In 
the  Brazils  a  species  popularly  called  the  Negro 
Head  makes  a  strange  nest,  as  round  as  the  negro's 
bullet-shaped  head,  and  exteriorly  covered  with  pro- 
jections, suggestive — with  a  little  stretch  of  the  imagi- 
nation— of  the  African's  close  woolly  hair.  It  is 
pensile  on  trees,  and  might  easily  be  mistaken  for 
the  pensile  home  of  certain  wasps.  Its  internal 
arrangements  prove  to  be  more  elaborate,  for  it  is 
ramified  with  multitudinous  covered  passages  inter- 
lacing intricately,  but  all  leading  to  the  interior  cells. 
Formica  elata  and  Myrmica  kirbii  also  carry  their 
abdomens  erect,  and  both  build  on  the  branches  of 
trees  and  shrubs.  The  nest  of  the  former  is  a  wonder- 
ful construction  of  earth  mixed  with  leaves,  which  in 
some  cases  are  exchanged  for  minute  vegetable 
hairs.  Myrmica  kirbii  makes  a  habitation  of  a 
congeries*  of  the  excrement  of  cows  and  mules 
spread  out  into  a  multitude  of  thin  folia,  which  are 
placed  one  upon  the  other  in  a  wavy  or  scalloped 
manner,  like  the  tiles  of  a  house,  leaving  numerous 
arched  entrances  beneath  the  flakes,  so  that  although 
the  insects  can  creep  into  the  nest,  no  water  can 
enter.  Over  the  summit  is  stretched  a  very  large 
flake  in  one  unbroken  sheet,  like  a  skull-cap  on  a 
man's  head,  which  acts  as  a  general  roof  and  projects 


152          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

on  all  sides  beyond  the  circumference.  The  edifice 
tends  to  become  spherical  or  balloon-shaped  ;  its  size 
is  about  that  of  an  ordinary  foot-ball.  A  vertical 
section  presents  an  innumerable  number  of  irregular 
cells,  composed  of  the  same  substance  as  the  exterior. 
Towards  the  centre  they  are  more  capacious  than 
near  the  surface,  and  have  been  found  to  contain 
insects  in  every  stage  of  development.  These  nests 
were  discovered  by  Colonel  Sykes  in  the  Poona 
Collectorate,  India,  attached  to  the  Kurwund  shrub 
(Carissa  carandas)  and  on  the  Mango  tree  (Mangifera 
Indica).  No  provision  for  the  young  appears  to  be 
laid  up,  and  probably  the  house -supplies  depend  on 
daily  quest.  The  ants  are  extremely  small,  barely 
one-fifth  of  an  inch  long. 

The  nests  of  another  extraordinary  tree  ant,  (Eco- 
phylla  smaragdina,  are  cunningly  wrought  with  leaves, 
united  together  with  web  (see  Fig.  24).  One  was  observed 
in  New  South  Wales  in  the  expedition  under  Captain 
Cook.  The  leaves  utilised  were  as  broad  as  one's  hand, 
and  were  bent  and  glued  to  each  other  at  their  tips. 
How  the  insects  manage  to  bring  the  leaves  into  the 
required  position  was  never  ascertained,  but  thousands 
were  seen  uniting  their  strength  to  hold  them  down, 
while  other  busy  multitudes  were  employed  within  in 
applying  the  gluten  that  was  to  prevent  them  returning 
back.  The  observers,  to  satisfy  themselves  that  the 
foliage  was  indeed  incurvated  and  held  in  this  form 
by  the  efforts  of  the  ants,  disturbed  the  builders  at 
their  work,  and  as  soon  as  they  were  driven  away  the 
leaves  sprang  up,  with  a  force  much  greater  than  it 
would  have  been  deemed  possible  for  such  labourers 


iv  SOCIAL  HOMES  153 

to  overcome  by  any  combination  of  strength.  The 
more  compact  and  elegant  dwelling  of  (E.  virescens  is 
made  of  leaves,  cut  and  masticated  until  they  become 
a  coarse  pulp.  Its  diameter  is  about  six  inches  ;  it 
is  suspended  among  thickest  foliage,  and  sustained 
not  only  by  the  branches  on  which  it  hangs, 
but  by  the  leaves,  which  are  worked  into  the  com- 
position, and  in  many  parts  project  from  its  outer 
wall.  It  may  be  at  once  distinguished  from  the  nest 
of  Crematogaster  by  its  smoothness  and  regularity  of 
surface.  A  species  of  this  genus  was  discovered  in 
Africa  by  Foxcroft,  who  observed  that  whenever  the 
ants  were  molested,  they  rushed  out  of  their  house  in 
such  numbers  that  their  pattering  upon  the  papery 
covering  deluded  him  into  thinking  rain  was  falling  on 
the  leaves  above. 

In  the  forests  of  Cayenne,  the  nests  of  F.  bispinosa 
are  remarkably  like  a  sponge,  or  an  overgrown 
fungus*.  The  down  or  cottony  matter  enveloping  the 
seeds  in  the  pods  of  the  Bombax  ceiba  is  used  for  their 
construction,  vegetable  fibres  that  are  too  short  to  con- 
vert into  fabrics,  but  which  the  ants  contrive  to  felt  and 
weave  into  a  compact  and  uniform  mass,  so  dexter- 
ously that  all  trace  of  the  individuality  of  the  threads 
is  lost.  The  material  much  resembles  amadou*,  and 
like  that  substance  is  valuable  for  stopping  violent 
discharges  of  blood.  In  size  the  nests  generally  have 
a  diameter  of  eight  or  nine  inches.  The  ant  itself  is 
little,  and  dark,  and  noted  for  two  long  sharp  spines 
on  its  thorax,  one  on  either  side  ;  hence  its  scientific 
name  of  bispinosa,  from  the  Latin  meaning  two-spined. 
Popularly  it  has  been  called  the  Fungus  Ant. 


CHAPTER  V. 

SOCIAL  HOMES  (continued). 

So-called  humble-bees— eighteen  or  twenty  species  in  this 
country — comparison  of  their  habitations  with  the  hive— 
Description  of  nest  of  Carder— the  coping  of  moss — interior 
— dispersion  of  company  and  hybernation  of  females — 
work  of  latter  in  spring — Deep  burrowers  among  British 
wild  bees— Honey-bees  in  the  East — Stingless  Meliponae 
and  Trigonas  of  South  America  and  their  homes — supposed 
presence  of  several  fertile  females— sentinels  to  guard  the 
gates — True  social  wasps — their  building  material  and  dis- 
position of  combs— Particulars  of  home  of  common  English 
wasp — British  tree-wasps — the  papery  envelope— Nest  of 
hornet — Description  of  combs  of  Polistes  and  Icarias  with- 
out cover — Apoi'ca  has  a  cover  but  not  distinct — Card-board 
makers— Wasps  as  honey-gatherers.  • 

LEAVING  the  marvellous  structures  of  the  hive  out  of 
the  question,  in  this  part  of  the  world  the  only  bee 
tribe  that  construct  homes  by  the  united  labour  of 
the  society  are  the  wild  so-called  Humble  Bees. 
Every  one  is  acquainted  with  them,  big-bodied,  and 
velvety,  and  heavy  flyers,  on  the  wing  emitting  that 
deep  sonorous  hum  that  has  earned  for  them  their 
popular  title  with  its  numerous  variations.  They  arc 
known  not  only  as  Humble,  but  as  Hummel,  Bumble, 


CHAP.  V 


SOCIAL    HOMES 


155 


Dumble,  Dumbledore,  or  Foggie,  according  to  the 
dialect  of  the  particular  locality.  Though  all  are 
denominated  indiscriminately  by  this  general  term, 


H 


FIG.  25.—  Comb  of  a  small  honey  bee  (Apis  Jloralis)  from  India,     (a)  The  small 
cells  for  the  workers  ;  (t>)  the  large  cells  for  the  drones. 


in   this  country   in  truth  there  arc  over  eighteen   or 
twenty  species  of  these  bees,  the  greater  part  of  which 


156          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

constitute  one  genus  Bombus.  Each  differs  some- 
what in  detail  of  habits,  and  almost  interminable 
varieties  are  exhibited  as  regards  size  and  colour. 
Yet,  except  in  the  case  of  some  of  the  more  promi- 
nent species,  they  are  not  easy  to  identify ;  naturally 
the  popular  mind  recognises  no  difference ;  therefore 
no  distinct  common  appellations  have  been  originated 
for  them,  and  unfortunately  it  becomes  necessary  to 
make  use  of  the  scientific  names.  Their  habitations 
are  rude,  the  number  of  inhabitants  too  is  small, 
sometimes  not  more  than  twenty,  and  rarely  exceeds 
two  or  three  hundred.  Again,  contrary  to  the 
custom  of  the  hive,  there  is  no  single  female  who 
permits  no  rival  to  divide  with  her  the  affection  and 
deference  of  her  subjects,  and  who  is  set  apart  for 
one  exclusive  function.  In  the  Humble  Bee's  colonies 
the  males,  females,  and  neuters*  so-called,  dwell  on 
terms  of  amicable  equality  together,  and  the  females 
share  in  the  ordinary  duties  of  building  and 
providing  for  the  needs  of  the  house.  The  males, 
however,  as  in  the  hive,  are  fewer  than  the  workers, 
and  idle,  and  when  once  they  venture  abroad 
seldom  return. 

The  nest  of  B.  muscorum  is  plentiful  enough,  but 
not  easily  found.  Usually  it  is  situated  in  open 
meadowrs  and  pastures,  sometimes  in  hedge-banks 
where  the  soil  is  entangled  with  roots,  at  the  borders 
of  copses,  or  among  moss-grown  stones.  It  occupies 
a  shallow  cavity  in  the  ground,  perhaps  half  a  foot  in 
diameter,  either  selected  ready-made  or  formed  by 
the  bees  with  great  labour.  Over  the  inconsiderable 
hollow  rises  a  low  vaulted  dome  or  roof  to  a  height 


v  SOCIAL   HOMES  157 

rarely  reaching  more  than  three  or  four  inches  above 
the  surface,  and  composed  generally  of  fragments  of 
moss    cleverly   woven    into   an    admirable    covering, 
made  to  harmonise  with  surrounding  objects  with  the 
view   of    concealing   it   from  curious   eyes.     Besides 
moss,     the    bee's    favourite     material    apparently— 
whence  its  name  muscorum,  "  of  the  mosses," — dead 
leaves,    grass,    fern-fronds,    and   other   matters    are 
frequently  adopted  where  moss  is  scarce  or  absent ; 
but  whatever  the  substance  may  be  it  is  within  easy 
reach,  for  the  bee  never  attempts  to  transport  any- 
thing from  a  distance.     The  material  is  prepared  for 
roofing  purposes  in  a  manner  similar  to  that  of  card- 
ing cotton  or  wool,  or  heckling  flax.     The  process 
consists   in  the   operator  carefully  disentangling  the 
fibre,  seizing  it  and  drawing  it  through  her  jaws  and 
forelegs,  subsequently  she  passes  it  under   her  body 
by  means  of  the  remaining  pair  of  legs,  forming  it  as 
she  does  so  into  a  small  ball  or  bundle  convenient  for 
carrying  home.     The  object  of  the  dome  is  obviously 
to  protect  and  hide   the  dwelling,  which  lies  at  the 
slight   depth   of    an    inch   or    two    beneath  the  soil. 
Although  the  moss    is    laid    down    in    considerable 
quantity  it  would  be  inefficient  to  exclude  rain ;  and  as 
a  rule   a   lining  is  added,  a  thick  coating  of  grayish- 
yellow  wax  similar  to  that  of  which  the  breeding- 
cells  are  made,  but  of  far  inferior  quality  to  the  wax 
of  the  hive,  rendering  the  interior  water-tight.      The 
entrance   to   the   nest    is    in  the    lower  part,  and  is 
generally  a  kind  of  tunnel  or  covered  way,  sometimes 
more  than    a  foot  long  and  half  an  inch  wide,  more 
effectually   concealing   the   abode   from   observation. 


158         ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

The  occasional  opening  at  the  top  seems  solely  for 
the  admission  of  air  and  warmth  ;  by  it  the  bees  are 
never  seen  to  enter  or  depart,  and  it  is  closed  at 
night  and  in  bad  weather. 

On  removing  the  domed  coping  of  moss  and 
bringing  the  interior  into  view,  a  different  scene  is 
presented  from  the  delicate  rows  of  hexagonal  cells 
which  go  to  form  the  finished  workmanship  of  the 
vertical  combs  of  the  hive.  In  their  place  there  are 
various  irregular  groups  of  oval  pale-yellow  bodies, 
arranged  horizontally  in  a  general  way,  the  groups 
being  more  or  less  pressed  together  and  connected 
by  slight  joinings  of  wax.  These  are  not,  as  one 
might  suppose,  the  work  of  the  old  proprietors  of  the 
nest,  but  the  silken  cocoons  spun  by  the  larvae  for  their 
pupae  life,  in  like  manner  as  the  larvae  of  other  bees. 
Some  of  them,  chiefly  those  occupying  the  lower 
combs,  stand  open,  indicating  the  completed  develop- 
ment and  escape  of  their  former  inmates.  Those 


FIG.  26. — Melipona  bees  gathering  clay  ;   rom  Bates. 

which  are  closed  at  their  upper  extremity  include 
immature  pupae  not  ready  for  their  final  metamor- 
phosis. Besides  these  bodies,  several  amorphous* 


v  SOCIAL    HOMES  159 

masses  of  dark-coloured  wax  are  perceived,  of  flattened 
globular  shape  and  various  dimensions.  Opening 
them,  a  number  of  eggs  or  grubs  encircled  with  a  paste 
made  up  of  pollen  and  honey  are  found.  These  are 
the  true  breeding  cells,  formed  mostly  by  the  mother, 
who  deposits  her  eggs  here,  and  stocks  the  young 


FIG.  27. — Home  of  Vespa  Norwegica. 

with  the  supply  of  sweet  food.  The  larvae  that  are 
hatched  from  the  eggs  exhaust  the  store  given  them 
before  they  are  full-grown ;  when  it  is  consumed  the 
mother  furnishes  her  little  ones  with  daily  provision 
until  the  days  of  their  larvahood  are  accomplished, 
and  they  spin  cocoons  for  the  coming  helplessness  of 
pupse.  The  number  of  eggs  or  grubs  contained  in  one 


160         ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

spheroidal*  mass  varies  from  about  three  to  about  thirty. 
Intermingled  with  the  breeding  cells  and  cocoons  at 
certain  times  of  the  year,  especially  on  the  sides  and 
in  the  middle  of  the  nest,  are  likewise  small  goblet-like 
vessels  filled  with  a  very  pure  honey.  They  consist 
of  cocoons  deserted  by  the  pupae,  but  it  falls  to  the  lot 
of  the  workers  to  refurbish  the  disused  cells  for  the 
fresh  purpose.  Fragments  of  silk  left  hanging  from 
the  orifices  at  the  emergence  of  the  young  bees  they 
cut  away,  and,  after  shaping  the  rims  a  little,  they 
strengthen  them  by  rings  or  elevated  tubes  of  wax, 
completing  the  renovation  of  each  cup  by  the  addi- 
tion of  an  internal  lining  of  the  waxen  material. 
The  stored  honey  may  serve  to  moisten  the  food  of 
the  larvae,  probably  it  also  acts  as  nourishment  to 
the  working  colony  when  prevented  by  unfavourable 
weather  from  seeking  it  abroad.  Occasionally  the 
bees  construct  receptacles  or  honey-pots  entirely  of 
wax. 

As  winter  approaches  these  communities  break  up 
and  perish,  a  few  fertile  females  or  queens  alone  surviv- 
ing, the  Methuselahs  of  their  short-lived  race.  In  utter 
solitude  and  in  a  state  of  torpor  they  lie  in  any 
convenient  crevice  ;  in  the  rotten  wood  of  decaying 
trees,  under  moss  in  woods,  or  turf,  in  haystacks,  in 
the  eaves  of  barns  and  outhouses,  seldom,  if  ever,  in 
the  nest  that  they  have  inhabited.  Awaking  with  the 
sunbeams  of  returning  spring  they  commence  a  life 
of  unceasing  labour.  Diligently  they  search  for  fit 
spots  for  nest-building,  or,  in  default  of  suitable 
cavities  that  would  in  some  degree  abridge  their  toil, 
each  bee  hollows  out  a  small  hole  for  herself.  The 


v  SOCIAL  HOMES  161 

moss-dome  being  built,  she  collects  quantities  of 
pollen  and  honey,  and,  when  the  hoarded  mass  is 
sufficient  for  a  beginning,  proceeds  therein  to  deposit 
some  eggs.  In  a  few  days  the  larvae  are  hatched, 
and  immediately  set  to  work  to  eat  the  food  on  which 
they  are  cradled.  Soon  they  become  full-fed,  and 
spin  their  cocoons,  and  rapidly  undergoing  their 
transformations  they  gnaw  off  the  tops  of  their  cells 
and  shortly  emerge  as  perfect  insects.  Invariably  the 
first  batch  of  offspring  are  workers,  who  aid  the 
queen  in  forming  the  colony.  On  them  devolves  the 
enlargement  of  the  nest,  and  they  assist  in  the  up- 
bringing of  their  juniors  in  the  home.  Young  males 
and  females  do  not  appear  until  the  season  has 
considerably  advanced. 

B.  lapidarius,  "  the  red-hipped  humble  "  of  Shake- 
speare, one  of  the  most  abundant  of  British  Bombi, 
has  a  preference  for  making  its  nests  beneath  stones. 
Under  compulsion  of  untoward  circumstances,  it 
forms  residences  in  the  earth,  like  the  common 
Humble  Bee.  The  burrows  of  B.  terrestris  are  often 
of  great  depth ;  no  moss  cover  is  manufactured,  but 
the  roof  is  lined  with  layers  of  wax.  In  internal 
construction  these  nests  do  not  differ  from  the  nest 
of  B.  muscorum.  As  a  rule  deep  burrowers  have  a 
population  twice  as  numerous  as  the  more  surface- 
building  Carders.  The  latter  are  greatly  influenced 
by  the  weather,  their  numbers  being  much  diminished 
by  a  wet  unfavourable  season,  but,  speaking  generally, 
an  autumn  company  seldom  exceeds  a  hundred  all 
told.  Of  all  the  Bombi  the  common  Humble  Bee  is 
the  most  prolific,  and  its  homes  contain  more  indi- 

M 


162         ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

viduals  than  those  of  any  other  species ;  between 
three  and  four  hundred  members  sometimes  apper- 
tain to  one  nest.  This  is  a  sparse  society  as  com- 
pared with  the  hive ;  but  the  honey-bee  is  much 
smaller,  and  its  cells  in  which  it  is  hatched  and 
nurtured  are  correspondingly  minute.  Those  of  the 
Humble  Bee  are  not  only  large,  they  are  set  very 
irregularly  and  occupy  extensive  space.  Cells 
capable  of  holding  an  assemblage  of  three  or  four 
hundred  form  a  great  group,  and  require  a  cavity  to 
contain  them  enormous  in  proportion  to  the  size  of 
the  excavators.  Underground-builders  seem  of  more 
vindictive  character  than  the  Carders,  and  appear  to 
resent  interference  with  some  ferocity.  Nests  of  the 
Carders,  on  the  other  hand,  may  be  taken  almost  with 
impunity. 

The  Honey  Bee  (Apis)  is  not  wild  in  this  country  ; 
in  the  East,  its  supposed  original  home,  it  exists  in 
this  state  in  great  abundance.  Apis  indica  and 
nigrocincta,  species  probably  in  general  domesticity 
in  India,  build  in  hollow  trees  or  crevices  in  rocks  ; 
as  opposed  to  Apis  dorsata,  which  likes  to  hang  its 
combs  from  the  undersides  of  boughs  of  trees  or 
rocks.  Apis  dorsata  is  perhaps  the  best  known  of 
Indian  honey-bees,  and  is  extensively  cultivated  in 
the  Himalayahs.  Probably  rocks  are  its  favourite 
natural  nest-sites,  where  it  is  sheltered  from  the 
weather  and  the  attacks  of  bears.  In  the  hills,  as 
every  one  knows,  these  quadrupeds  make  almost  any 
effort  to  get  at  the  combs  and  honey  in  trees,  caring 
little  for  the  stings  of  the  defrauded  creatures. 
Numbers  of  nests  constantly  hang  from  old  buildings, 


v  SOCIAL  HOMES  163 

such  as  the  Taj  Mehal  at  Agra,  which  is  much  dis- 
figured with  the  pendant  combs.  Many  attempts  to 
remove  them  have  been  made,  but  no  sooner  is  a  nest 
destroyed  than  it  is  quickly  renewed  at  a  few  feet 
distant.  A.  floralis,  a  beautiful  little  bee,  nidifies  on 
the  branches  of  orange  and  lemon  trees,  and  garden 
shrubs  generally  (see  Fig.  25),  occasionally  in  the 
interior  of  mud  walls,  the  cavities  between  bricks, 
or  in  holes  excavated  by  the  termites  or  white 
ants.  Immense  clusters  of  honey-combs  hang  in  the 
caves  of  Salsette  and  Elephanta,  in  the  clefts  of  the 
rocks  and  the  recesses  among  the  figures.  So  abund- 
ant are  the  bees,  they  have  been  known  to  put 
intrusive  visitors  to  the  rout. 

From  Europe,  long  ago,  the  Honey  Bee  (Apis)  was 
imported  into  the  West  India  Isles  and  the  northern 
provinces  of  South  America,  where  it  exists  at  the 
present  day  domesticated,  and  at  large  in  the  woods 
and  forests.  Not  a  single  species  of  this  restricted 
genus  is  indigenous  to  the  country.  In  North 
America  the  nearest  ally  as  regards  its  habits  is  the 
Humble  Bee,  of  which  no  fewer  than  forty  species 
are  known.  The  tropics  possess  considerably  better 
substitutes  in  the  genera  Melipona  and  Trigona,  the 
celebrated  stingless  honey-bees  of  South  America. 
The  Meliponce  have  remarkably  long  legs,  they  are 
short  and  squat,  generally  much  smaller  than  the 
hive  bee,  some  in  fact  are  nearly  as  tiny  as  midges, 
and  extremely  irritating  for  getting  into  the  nostrils 
and  about  the  head.  Though  they  have  no  sting,  or 
rather  their  sting  is  feeble  and  they  use  it  seldom — 
whence  the  Spaniards  call  them  angelitos,  or  little 

M  2 


1 64         ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

angels — they  appear  capable  of  biting  sharply.  Their 
colonies  are  often  far  more  numerous  than  those  of 
the  Apides,  and  several  fertile  females  are  said  to  live 
together  in  harmony.  They  construct  homes  in 
suitable  crevices  in  hollow  trunks,  or  in  perpendicular 
banks,  even  in  cavities  of  rocks  by  the  sea-shore. 
The  form  of  the  habitation  varies  according  to  the 
species,  but  most  kinds  of  Meliponce  are  masons.  It 
would  appear  that  the  Old  World  has  produced  far 
more  advanced  forms  of  animal  life  than  the  tropics 
of  the  New  World,  and  these  bees  offer  no  exception 
to  the  rule.  Their  nests  may  be  of  enormous  pro- 
portions, and  immense  quantities  of  pollen  and  honey 
are  stored,  yet  their  architecture  is  very  inferior  to  the 
skill  exhibited  in  the  European  hive.  The  Melipona 
are  as  prodigal  of  wax  as  the  others  are  sparing  of  it. 
Their  comb  is  composed  of  a  single  series  of  alveoli  * 
applied  laterally  to  each  other,  and  not  of  two  strata 
or  layers  placed  end  to  end.  Generally  they  are 
oblong,  showing  only  here  and  there  an  approxima- 
tion to  the  elegant  hexagonal  shape,  and  appear  to 
be  destined  solely  as  the  residences  of  the  larvae. 
The  honey  is  stored  apart  from  the  brood-cells  in 
great  waxen  vases  or  vesicles,  with  thick  and  strong 
walls.  Some  of  these  sacs  have  a  diameter  of  an 
inch  and  a  half,  or  about  as  large  as  a  pigeon's  egg. 

The  most  numerous  and  interesting  masons,  Meli- 
pona  fasciculata,  are  about  one-third  shorter  than  Apis 
mellifica.  Little  crowds  of  the  workers  are  constantly 
employed  in  gathering  clay,  and  the  rapidity  and  pre- 
cision of  their  movements  while  thus  engaged  are 
wonderful  (see  Fig.  26).  With  the  material  collected 


v  SOCIAL  HOMES  165 

they  construct  a  wall,  often  in  the  hollow  of  a  tree, 
filling  up  the  crevice  with  the  exception  of  a 
narrow  orifice.  One  species,  still  more  determined 
to  secure  safety  and  privacy,  in  addition  to  blocking 
up  the  gap,  fashions  a  neat  tubular  gallery  of  clay 
outside  its  doorway;  the  tube  has  a  trumpet-shaped 
mouth,  and  the  particles  are  kneaded  together  with 
some  substance  of  viscid  consistency.  At  the  entrance 
a  number  of  the  pigmy  owners  are  always  stationed, 
apparently  acting  the  part  of  sentinels.  That  these 
bees  appoint  sentinels  to  guard  their  gates  is  a  fact  of 
frequent  observation.  They  sedulously  watch  the  out- 
goings and  incomings  of  their  fellows,  and  seem  now 
and  then  to  be  relieved  on  duty.  A  relief-guard  pre- 
sents itself  every  twenty-four  hours  according  to  the 
Mexican  cultivators,  but  no  unreasonable  doubts  may 
be  entertained  of  such  regularity.  At  all  times  the 
sentinel-bee  occupies  the  hole  leading  to  the  interior, 
and  as  often  as  a  worker  desires  to  enter  or  to  quit  the 
nest,  momentarily  withdraws  within  a  small  cavity  on 
the  side  of  the  aperture,  resuming  its  station  with  sur- 
prising alacrity  whenever  the  individual  has  passed  in 
or  out.  In  Jamaica,  where  probably  the  species  are  simi- 
lar, if  not  identical  with  those  of  Mexico  and  the  Brazils, 
no  fewer  than  three  sentinels  have  been*  seen  oppos- 
ing the  entry  of  the  black  ants  that  infest  forest 
trees.  The  assistants  stood  behind  their  principal, 
heads  downwards,  and,  clinging  to  the  upper  arch  of 
the  entrance,  they  gazed  upwards,  steadily  scanning 
several  ants  within  the  crevices  of  the  bark,  prepared 
to  rush  in  if  the  guards  remitted  their  vigilance  for  one 
moment.  The  active  ants  paced  upwards  and  down- 


166         ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

wards  in  lines,  eager  for  the  booty,  but  were  allowed 
no  greater  satisfaction  than  a  rapid  reconnoitring  of 
the  doorway.1 

Bees  of  the  genus  Trigona  hang  their  combs  out- 
side on  the  branches  of  trees,  at  the  very  summit  of 
the  tree  and  the  end  of  the  slenderest  twig,  so  as  to 
be  out  of  the  reach  of  the  monkeys.  In  shape  the 
nests  are  like  a  large  pear,  and,  judging  by  the  dimen- 
sions of  some  and  the  multitudes  inhabiting  them, 
it  seems  hardly  possible  to  doubt  that  they  contain 
several  prolific  females,  as  in  the  Meliponce.  While 
the  Meliponce  are  chiefly,  or  exclusively,  restricted  to 
the  warm  regions  of  the  New  World,  the  Trigonce 
extend  into  India,  Africa,  Australasia,  and  to  the 
Isles  of  the  Eastern  Archipelago.  The  honey  of 
some  species  is  sweet  and  altogether  excellent,  that 
of  others  is  black  and  sour  and  quite  worthless,  but 
dark  honey,  as  of  Trigona  ruficornis^  may  be  well 
flavoured.  The  wax  too,  is  sometimes  very  dark  and 
unctuous,*  though  susceptible  of  being  whitened 
somewhat  by  bleaching. 

The  hives  for  domesticating  the  Meliponce  in 
Mexico  are  primitive,  and  follow  closely  the 
habitat  of  the  bee  in  a  state  of  nature,  being  simply 
a  portion  of  a  hollow  log  of  between  two  and  three 
feet  long;  a  hole  is  bored  into  the  interior  through 
the  sides  midway  down  the  length,  and  the  ends 
are  stopped  with  clay.  They  are  usually  sus- 
pended on  trees  in  a  horizontal  position,  and  are 
quickly  taken  possession  of  by  bees.  While  some 
of  the  combs  are  vertical,  others  are  situated  hori- 
1  Naturalist's  Sojourn  in  Jamaica.  Gosse. 


SOCIAL  HOMES 


167 


zontally,  the  cells  of  the  latter  being  the  most 
numerous ;  all  are  ranged  together  at  some  distance 

from  the  opening. 
Externally  to  these 
are  the  clusters  of  sacs 
for  the  honey,  affixed 
to  the  wood  of  the 
cavity  by  processes 
of  wax,  or  to  each 

FIG.  28. — Comb  of  Polistes  tepidus,  Fabr. ,  with     other    and    frCQUentlv 
centre  pedicle  ;  from  Saussure.  J 

placed  side  by  side  ; 

the  disposition  of  a  group  as  a  whole  has  some 
resemblance  to  a  bunch  of  grapes.  Taking  advantage 
of  the  irregular  position  of  the  sacs,  the  cultivators 
abstract  the  honey  by  removing  the  clay  plug  from 
the  bottom  of  the  hive,  and  secure  the  riches  without 
injuring,  almost  without  disturbing,  the  inmates. 
The  end  is  again  closed,  and  the  bees,  robbed  of  their 
treasure,  lay  in  a  fresh  store. 

The  true  social  Wasps,  which  are  arranged  in  one 
large  family,  the 
Vespidce,  form 
communities.whose 
architectural  la- 
bours will  not 
suffer  on  compari- 
son even  with  those 
of  the  inhabitants 
of  the  bee-hive. 
In  fact,  for  dainti- 
ness and  delicacy  the  nests  of  many  of  the 
Vespidce  constitute  the  most  beautiful  examples 


FIG.  29. — Comb  of  Polistes  cctnadensis,  Linn, 
inverted,  with  lateral  support  and  irregular  cells 
many  still  containing  nymphs  ;  from  Saussure. 


i68         ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

of  insect  architecture.  As  with  the  bees,  the  great 
object  of  their  industry  is  the  safety  and  upbringing 
of  their  beloved  young,  and  in  like  manner  they 
construct  combs  for  their  reception,  consisting  nearly 
always  of  hexagonal  cells.  The  building  material 
they  employ,  however,  is  totally  dissimilar  to  wax, 
and  the  plan  of  their  city  differs  from  that  of  the 
hive.  These  nests  show  many  discrepancies,  and 
their  situations  vary;  but  though  they  are  heteroge- 
neous in  detail,  in  the  essential  and  most  important 
points  they  are  all  alike. 

The    common     English    Wasp     (Vespa   vulgaris) 
is    a  handsome  insect,   much    disliked   for  its    fond- 
ness    for     everything     sweet    and     its     formidable 
weapon  of  defence.     The  gardener  especially  holds 
it  in   abhorrence,  on  account  of  its  depredations  on 
fine  ripe  fruit.     Still  it  is  more  a  predacious  than  a 
vegetable  feeder,  and  the  evil  it  commits  in  respect 
of  the  peaches,  and    so   on,   is    perhaps    more    than 
counterbalanced   by  its  good  works  in  ridding  us  of 
many  a  tiresome  fly  and  similar  pest.     Usually  situ- 
ated in  a  cavity  underground,  the  nest  is  a  marvel  of 
ingenious  industry.     Of  more  or  less  globular  shape, 
and  about  sixteen  to  eighteen  inches  long  by  twelve 
or    thirteen    broad,    it    is    inclosed    in    a   coating   of 
material  some  half  an   inch  thick,  like  coarse  brown 
paper,  though  not  so  tough,  made  up  of  numerous 
thin  leaves  or  laminae,  which  do  not  touch  but  have 
small   intervals  between   them,   and  is  evidently  in- 
tended to  prevent  the  earth  from  getting  among  the 
combs  inside.      If  this  external  portion  is  removed 
the   combs   are   exposed,   generally   from  twelve   to 


v  SOCIAL  HOMES  169 

fifteen  in  number,  circular,  and  of  different  sizes, 
and  disposed  horizontally  in  distinct  and  parallel 
tiers  one  above  the  other.  Each  consists  of  an  as- 
semblage or  layer  of  cells  of  papery  stuff  like  the 
covering,  their  mouths  directed  downwards,  so  that 
their  upper  ends  or  bases,  which  are  slightly  convex, 
together  constitute  an  almost  level  floor,  on  which  the 
wasps  conveniently  pass  to  and  fro  in  attendance  on 
the  young  hanging  in  the  comb  of  cells  immediately 
above.  These  terraces  are  supported  by  fixture  to 
the  sides  of  the  nest,  and  each  is  attached  to  the  pre- 
ceding one  by  cylindrical  columns  or  pillars,  of  a 
compact  paper.  Access  from  tier  to  tier  is  gained  by 
openings  between  the  walls  of  the  combs.  At  the 
bottom  of  the  nest  two  main  holes  exist,  the  entrance 
and  exit  ways  common  to  the  community.  A 
covered  road  leads  from  the  surface  to  the  subter- 
ranean dwelling,  often  a  long  and  tortuous  path,  an 
approach  carefully  concealed  though  well-known  to 
the  miners. 

This  wonderful  structure  arises  from  a  small  begin- 
ning. In  the  early  spring  a  solitary  wasp  or  two 
may  be  observed  here  and  there,  flying  neither  high 
nor  fast,  but  plainly  on  a  tour  of  inspection  of  the 
earth-banks,  scrutinising  into  the  opportunities  they 
offer  for  the  formation  of  a  home.  These  are  females 
who  have  just  awakened  from  their  hybernation.  At 
last  the  wasp  meets  with  a  crevice  to  her  mind, 
the  abandoned  burrow  of  a  field-mouse  maybe,  or  of 
a  mole,  or  perhaps  the  forsaken  tunnel  of  some  large 
burrowing  insect.  She  examines  it  in  every  par- 
ticular, she  fusses  in  and  out,  she  appears  to  delibe- 


i;o         ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

rate  ;  eventually  she  assumes  proprietorship,  and  pre- 
pares to  enter  into  possession.  The  first  thing  to  be 
done  is  to  form  a  chamber  to  her  liking  at  some  dis- 
tance below  the  surface  ;  so  she  breaks  away  the  soil, 
and  carries  or  pushes  it  out  bit  by  bit.  The  cavity 
being  ready,  the  next  item  of  procedure  is  to  lay  the 
foundations  of  the  house  to  be  included,  which  con- 
trary to  the  usual  custom  of  builders  is  begun  at  the 
top.  Taking  leave  of  the  home-site  for  a  time,  she 
flies  off  to  a  wooden  post,  or  rail,  a  window-frame,  or 
some  such  thing,  where  with  her  jaws  she  busily 
gnaws  away  the  fibres  until  she  amasses  a  little 
bundle.  She  kneads,  and  triturates,  and  moistens 
the  filament  with  saliva,  reducing  it  to  a  homogeneous 
paste  or  pulp,  a  kind  of  papier-mac] te.  Back  to  the 
nest  she  hurries  with  her  burden.  Here  the  ductile 
mass  is  made  to  adhere  to  the  centre  of  the  ceiling  of 
the  chamber  by  her  jaws  and  forefeet ;  meanwhile  she 
clings  to  the  ceiling  by  her  two  last  pairs  of  legs. 
Supply  after  supply  is  acquired  and  placed,  until  a 
pillar  about  half  an  inch  long,  pendant  from  the  ceil- 
ing, is  complete.  At  the  extremity  of  the  pillar,  with 
the  same  material  and  in  like  manner,  she  attaches 
three  very  shallow  cylindrical  cup-like  cells,  in 
depth  about  a  tenth  of  an  inch.  They  hang  bell- 
wise,  and  in  each  she  deposits  an  egg.  The  young 
things  require  protection,  and  over  them  the  mother 
simultaneously  constructs  a  roof,  umbrella-shaped, 
and  made  of  paper  as  the  cells,  but  laid  differently, 
the  length  of  the  fibres  being  almost  at  right  angles 
to  the  middle  of  the  proposed  comb.  On  either  side 
of  the  first  group  cells  are  added  close  together  on 


SOCIAL  HOMES 


171 


the  horizontal  floor,  eggs  are  laid  in  them,  and  in 
correspondence  with  the  enlargement  the  roof  is 
extended.  The  covering  is  of  considerably  rougher 


FIG.  30. — Nest  of  Icaria  variegatci, 

texture  than  the  cells,  and  no  attempt  is  made  to 
smooth  the  surface. 

By  this  time   the  three  eggs  that  were  first  laid 


172          ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

are  hatched,  and  the  larvae  have  to  be  fed  ;  they 
increase  in  size,  and  their  cradles  must  needs  be 
bigger.  The  poor  mother  finds  plenty  to  do, — she 
has  to  construct  cells,  to  lay  eggs,  to  enlarge  the  cell- 
walls,  and  to  seek  for  food  wherewith  to  satisfy  her  more 
advanced  offspring.  Soon,  however,  the  worst  of 
her  troubles  are  over.  The  first-born  become  full- 
grown,  cease  to  feed,  and  inclose  themselves  within 
their  cells,  each  in  its  own  white  silky  cocoon  with 
convex  cap,  and  shortly  emerge  as  perfect  insects. 
The  work  now  goes  merrily  on,  for  these  young  wasps 
are  workers,  who  take  upon  themselves  the  arduous 
share  of  the  labours  of  the  hive.  They  increase  its  ex- 
tent, and  become  nurses  to  their  younger  companions, 
while  the  mother  does  little  but  lay  eggs  in  cells  as 
fast  as  they  are  made.  As  time  goes  on  brood  after 
brood  of  recruits  is  added  to  the  army  of  workers,  new 
cells  rise  quickly,  and  are  as  quickly  supplied  by  the 
mother,  and  before  long  the  first  cell-terrace  is  com- 
pletely filled. 

Various  pendant  pillars,  similar  to  the  foundation 
pillar,  now  appear  on  the  underside  of  the  comb  at 
the  angles  where  these  cells  meet.  To  their  extremi- 
ties cells  are  caused  to  adhere,  and  by  dint  of  additions 
they  soon  all  unite  and  form  a  second  terrace  below 
the  first,  the  distance  between  the  two  tiers  being 
about  half  an  inch,  or  equal  to  the  height  of  the  inter- 
vening columns.  A  third,  a  fourth,  and  a  fifth  tier 
are  constructed,  and  the  roof  or  walls  of  the  building 
are  constantly  brought  down  lower.  The  cells  com- 
posing the  foundation  terraces  are  amongst  the 
smallest  in  the  completed  nest;  they  are  too  small  to 


v  SOCIAL  HOMES  173 

admit  the  head  of  the  female,  who  when  she  gives  the 
inmates  mourishment  feeds  them  entirely  from  the 
outside.  It  follows  that  the  wasps  bred  in  them  must 
be  of  less  size  than  the  mother,  they  are  indeed  all  un- 
developed females  or  workers.  The  cells  of  the  next 
few  tiers  are  much  larger,  being  the  breeding-places 
of  the  males  and  females.  Thus,  then,  workers  only 
are  brought  forth  early  in  the  season  ;  the  males 
are  hatched  subsequently,  and  the  virgin  females 
latest  of  all.  The  terraces  gradually  increase  in 
diameter  up  to  the  fourth  or  fifth,  when  they  usually 
decrease  slightly,  and  in  exact  conformity  with  this 
formation  the  covering  is  constructed.  They  are  not 
perfectly  perpendicular  but  somewhat  raised  at  the 
corners,  so  as  to  form  a  trifling  concavity  in  the 
centres  of  the  floors.  Though  the  cells  are  cup-shaped 
at  their  bases,  they  become  beautifully  hexagonal  as 
they  rise  in  height,  or  rather  in  depth,  particularly  at 
the  middle  of  the  combs  ;  a  large  nest  contains  from 
about  7,000  to  10,000.  Each  is  believed  to  be  the 
birthplace  of  three  generations,  with  the  exception  of 
those  intended  for  the  males  and  females  which  are 
probably  the  cradles  of  but  one  brood.  Wood  fibres 
seem  a  flimsy  substance  of  which  to  make  such  an 
edifice,  and  by  which  to  sustain  so  great  a  multitude, 
but  as  a  fact  the  walls  are  very  strong,  and  the 
hexagonal  shape  of  the  cells  affords  mutual  support. 
Scarce  is  the  building  finished  ere  it  begins  to  show 
signs  of  dissolution.  The  summer  is  over,  the  several 
broods  of  workers  have  passed  through  the  cells,  and 
the  single  generation  of  males  and  females  have 
become  mature.  The  males  are  dead,  the  workers 


174 


ROMANCE  OF  THE  INSECT  WORLD      CHAP. 


likewise  desert  the  home  and  die,  and  the  majority 
of  the  females,  a  few  only  seeking  refuge  in  cracks 
and  holes,  where  they  survive  the  winter,  and  live  to 
be  queens  and  founders  of  future  colonies.  Out  of  a 
vespiary  holding  three  hundred  females  in  the  autumn, 
barely  ten  or  twelve  will  see  the  spring.  Before 
deserting  the  cells  should  any  grubs  remain  un 


FIG.  31.— Nest  of  a  Brazilian  Wasp  (Apotca  pallida). 

developed,  the  workers,  apparently  prescient  of  their 
coming  doom  and  aware  that  there  will  be  none  to 
discharge  the  duties  they  must  themselves  lay  down, 
carry  forth  the  helpless  nurslings  and  forsake  them, 
— arrant  cruelty  on  the  face  of  it,  in  reality  an  act  of 
mercy,  substituting  a  quick  death  by  exposure,  or  by 
falling  a  prey  to  some  creature's  appetite,  for  the  slow 


v  SOCIAL  HOMES  175 

lingering  death  by  starvation  that  would  be  theirs 
were  they  left  neglected  within  the  nest. 

Occasionally  V.  vulgaris  dispenses  with  a  burrow, 
and  builds  from  beams  in  the  corners  of  outhouses  ; 
under  a  thatched  roof  is  also  a  favourite  locality. 

Among  the  British  Tree  Wasps,  which  habitually 
make  pensile  nests,  the  best  known  is  Vespa  Britan- 
nica.  In  the  South  and  West  of  England  it  is  rare, 
but  is  plentiful  in  Scotland.  Its  lovely  globe-like 
dwellings  it  boldly  suspends  from  the  extremities  of 
branches  of  trees  and  shrubs,  chiefly  the  fir  and  the 
gooseberry.  V.  sylvestris  has  a  wider  distribution, 
but  is  scarcely  so  common,  and  is  a  burrower  at 
times.  The  outer  shell  or  envelope  of  the  pensile 
nest,  very  fine  and  choice  in  relation  to  the  covering 
of  the  subterranean  combs  of  the  common  wasp,  is 
made  of  a  smooth  and  white-gray  paper,  its  individual 
flakes  being  sharply  defined.  It  is  impervious  to 
water,  and  protects  the  combs  admirably,  to  which 
however  it  is  never  attached.  The  opening  is  at  the 
lowest  part,  and  underneath,  and  is  sufficiently  large 
to  give  free  entrance  and  exit.  For  beauty,  delicacy, 
and  utility,  the  Tree  Wasp's  nest  is  unrivalled  (see 
Fig.  27). 

As  the  population  of  a  wasp  community  increases 
and  the  cells  must  be  augmented,  laborious  is  the 
undertaking,  since  it  necessitates  that  the  inner  sheets 
of  the  covering  be  cut  away  to  make  room  for  the 
greater  size  of  the  comb,  or  combs,  while  faster  than 
these  are  removed  additional  layers  are  formed 
externally,  to  maintain,  and  even  to  slightly  add  to, 
the  thickness  of  the  walls.  Thus  is  the  human 


i?6         ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

architect  careful  to  proportion  the  thickness  and  con- 
sequently the  strength  of  his  walls,  to  the  magnitude 
of  the  building  about  to  be  erected.  This  method  of 
enlargement  of  the  nest-cover  obtains  among  the 
species  sylvestris,  Norwegica,  and  rufa.  In  the  case 
of  the  subterranean  dwellers,  vulgaris  and  Germanica, 
and  among  the  hornets,  the  mode  consists  not  in  the 
superposition  of  layers,  hollow  pieces  of  material  are 
formed,  blisters,  as  it  were,  are  raised  all  over  the  plain 
outer  surface  as  left  by  the  queen  when  she  renounced 
her  architectural  labours.  Blister  after  blister  is 
placed  one  above  the  other,  and,  as  in  the  former 
instance,  the  underlying  matter  is  cut  away  nearly  as 
quickly  as  the  fresh  formation  is  added.  The 
material  removed  is  not  discarded  as  useless,  but 
worked  up  afresh ;  as  a  fact,  this  is  performed  by  the 
act  of  removal.  Subsequently  it  serves  both  for  new 
cells  and  for  additions  to  the  outside.  The  alteration 
of  a  subterranean  dwelling  involves  the  greatest  toil, 
for  besides  the  changes  necessary  in  the  envelope 
plainly  the  area  of  the  nest-cavity  must  be  enlarged. 
Care  is  always  taken  to  keep  free  a  clear,  though 
tiny,  space  between  the  papery-shell  and  the  earth 
interior. 

The  fabrication  of  the  papery  sheets  that  together 
make  up  the  powerful  envelope  is  a  perfect  work  of 
art.  One  is  astonished  at  their  resemblance  to  our 
own  gray  paper.  This  paper  is  simply  thinner,  more 
silky,  more  smooth  and  glossy ;  it  offers  great  analogy 
to  papers  made  by  island  savages  from  the  bark  of 
trees.  When  a  wasp  bears  a  fibrous  ball  of  paste  to 
the  nest,  and  adds  it  to  that  piece  of  the  covering  on 


v  SOCIAL  HOMES  177 

which  the  builders  are  engaged,  it  draws  out  the  little 
mass  with  its  jaws  and  feet  into  ribbon-like  form  along 
the  edge  of  the  wall,  reducing  it  to  the  requisite  thin- 
ness   much  as  a    mass  of   metal   is  pressed  by   the 
cylinders  of  the   rolling-mill.     During  the  operation 
the  wasp  invariably  walks  backwards.      The  tongue 
then  adds  the  finishing  touches,  giving  the  paper  a 
brightness  and  polish.     A  colony   labour  simultane- 
ously,   and  the  workers   bring  their  morsels  to    the 
same  point  of  the  nest,  resulting  in   a  regular  trans- 
verse zone.     Every  nest  shows  these  zones  of  forma- 
tion of  the  paper,  sometimes  not  very  distinct  because 
they  vary  simply  from  darker  to  lighter  tones  of  gray  ; 
but  often  the  stripes  are  quite  pronounced  and  of  dif- 
ferent colours.    The  wasps  go  forth  solitarily  in  search 
of  building  material  no  doubt,  and  must  bring  in  stuffs 
of  various  sorts.    But  when  one  finds  a  good  working- 
stock,  others  seem  to  become  cognisant  of  the  fact  and 
hasten   to  the  spot,  and  the  zone  constructed  will  be 
of  a  particular  colour.    If,  for  example,  a  birch  be  the 
object  attacked,  the  zone  will  be  white ;  if  a  poplar,  the 
zone  will  be  green.    The  same  wasp,  however,  it  has 
been  observed,  does  not  always  bring  in  a  load  of  the 
like   colour.     But  she  seems  sensible  enough  not  to 
deposit  her  lump  behind  material  different  from  her 
own,  she  puts  it  against  similar  substance,  and  mixed 
bands  are  never  made. 

The  separate  sheets  or  leaves  of  paper  are 
not  complete  sacs,  shutting  in  the  combs  as  an 
egg  is  inclosed  in  its  shell.  They  are  limited 
in  size  and  imbricate*  with  one  another,  and  are 
kept  in  place  and  are  in  contact  together  merely 

N 


i;8          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

at  the  points  of  imbrication.  Flat  cell-like  spaces 
occur  between  them,  except  towards  the  summit 
of  the  nest  where  the  envelope  forms  a  thick- 
ish  compact  mass.  The  points  of  fusion  of  two 
successive  layers  never  fall  precisely  the  one  above 
the  other.  By  this  mode  of  construction  each  layer 
of  paper  lies  on  a  stratum  of  air,  a  disposition 
that  withstands  inclemency  of  weather.  The.  whole 
of  the  exterior  layers  may  be  soaked  with  rain 
without  soiling  in  the  slightest  the  leaves  beneath. 
The  paper  of  Vespa,  though  sticky,  is  not  varnished, 
and  wets  easily.  But  it  will  dry  in  the  sun,  and  not 
be  in  the  least  deteriorated. 

The  nest  of  the  Hornet  ( V.  Crabro)^  tolerably 
plentiful  in  many  parts  of  England,  is  identical  in 
character  with  that  of  the  wasp.  It  is  larger  than 
the  wasp's  nest  and  the  cells  are  larger  ;  its  paper  is 
rougher,  and  the  columns  that  support  the  comb- 
tiers  are  higher  and  more  massive,  the  central  one 
especially,  which  is  about  twice  as  thick  as  any  of 
the  others.  This  insect  does  not  favour  the  under- 
ground for  a  dwelling;  it  lodges  in  out-of-the-way 
corners  in  thatch  or  under  the  eaves  of  barns  and  out- 
houses, and  is  extremely  partial  to  save  itself  trouble 
by  building  within  old  tree-trunks  hollow  from  decay. 
The  cavity  need  not  be  particularly  large  when  it  is 
adopted,  for  the  hornet  is  liberally  provided  with  the 
means  of  excavation  in  its  sharp  and  powerful  jaws. 
A  nest  so  situated  has  no  definite  papyraceous 
envelope,  the  hornets  seem  to  understand  perfectly 
that  the  wood  with  which  the  combs  are  surrounded 
affords  sufficient  protection  in  itself,  and  they  provide 


v  SOCIAL  HOMES  179 

coverings  only  for  those  parts  that  are  more  or  less 
exposed.  Thus  the  entrance  hole  is  always  obstructed 
by  leaves  of  paper  which  close  it  as  much  as  possible 
without  impeding  the  way  out.  Under  other  circum- 
stances hornets  are  at  great  pains  to  shelter  their 
combs  within  a  papery  coating  of  many  thicknesses, 
an  envelope  that  constitutes  an  excellent  example  of 
the  appearance  produced  by  obtaining  strength  of 
walls  and  large  dimensions  of  comb-tiers  by  constant 
exterior  additions  of  puffed-out  papery  cells.  They 
open  on  the  surface  of  the  nest,  where  they  are  very 
regular,  by  narrow  entrances,  always  directed  down- 
wards, the  object  being  doubtless  to  prevent  any 
substance  falling  from  above  from  penetrating  inside. 
Saussure  believes  the  use  of  these  entrances  is  to 
permit  the  access  and  circulation  of  air  amid  the 
vacuities  of  the  envelope,  for  the  purpose  of  drying 
the  papery  leaves  each  time  that  they  are  wetted  and 
softened  at  the  surface.  The  real  entrance  to  the  nest 
is  at  the  inferior  extremity,  as  in  other  Vespse  that 
nidify  in  the  open  atmosphere. 

When  hornets  take  up  domicile  within  a  hollow 
trunk  they  frequently  seem  to  make  no  use  of  the 
large  hole  of  the  tree,  but  go  to  the  trouble  of  digging 
a  gallery  through  some  undecayed  portion  It  assumes 
a  winding  direction,  and  probably  protects  the  nest 
from  intrusion.  In  the  opinion  of  Reaumur,  hornets 
can  distinguish  a  rotten  tree,  to  all  appearances 
healthy.  They  bore  through  the  sound  wood  to  reach 
the  interior,  and  gnaw  the  cavity  to  suit  their  con- 
venience. This  penetration  of  the  living  matter  is 
difficult,  and  the  hole  is  never  enlarged  beyond  the 

N    2 


i8o          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

limits  necessary  to  admit  of  free  locomotion  in  and  out. 
The  materials  removed  in  excavation  go  to  form  the 
cells,  and  the  coverings,  what  coverings  there  be.  Some 
of  the  nests  are  of  great  size,  even  three  feet  long, 
and  wonderfully  fragile,  due  to  the  choice  of  rotten 
wood  for  the  manufacture ;  whereas  other  wasps  scrape 
their  vegetable  fibres  from  moist  living  sources,  and 
make  a  firm  and  tenacious  structure.  The  hornet's 
paper  is  very  friable,  and  excessively  yellowish  or 
russet-coloured,  widely  different  from  the  silvery-gray 
composition  for  instance  of  Vespa  Norwegica.  In 
a  sense  the  hornet  is  more  indefatigable  than 
the  wasp.  At  night  the  wasp  retires  within  doors 
for  sleep,  but  if  the  moon  be  up,  the  hornet  steadily 
pursues  her  tasks ;  even  when  the  moon  deserts 
her,  she  is  prone  to  do  night-work. 

Leaving  Vespa  we  pass  to  the  Polistes,  a  group  of 
wasps  with  elongated  bodies  and  the  first  segment  of 
their  abdomen*  drawn  out  into  a  long  pedicle.  This 
genus  is  essentially  exotic,  though  it  occurs  sparingly 
in  England.  Their  system  of  nidification,  while  in- 
ferior to  Vespa,  far  exceeds  that  of  the  latter  in 
diversity  of  plan.  The  nests  differ  in  shape,  and  are 
very  variable  as  much  for  size  as  for  mode  of  attach- 
ment, but  the  combs  are  always  destitute  of  any 
covering  envelope  ;  the  young,  however,  are  perfectly 
safe  inside.  The  position  of  the  nests  is  not  purely 
horizontal,  but  oblique*  or  vertical,  so  that  they  are 
adapted  to  casting  off  the  rain.  If,  on  the  contrary, 
the  cells  faced  upwards  they  would  fill  with  water  ; 
were  they  directed  downwards  the  water  must  lie  on 
their  bases  as  on  a  flat  roof,  and  in  course  of  time 


v  SOCIAL  HOMES  181 

must  sink  through.  The  insects  take  the  further 
precaution  of  turning  them  towards  the  north  or 
north-east,  because  during  the  summer  and  autumn 
in  these  climates  the  strong  cold  winds,  and  those 
that  bring  rain,  usually  come  from  the  opposite 
quarter.  Their  impermeability  is  increased  by  a 
varnish,  probably  a  glutinous  liquor,  secreted  by  the 
wasps,  which  is  well  rubbed  on  to  the  papery  sur- 
faces. 

Though  each  species  seems  to  have  a  form  of  nest 
which  it  favours,  still  one  hard  and  fast  line  is  by  no 
means  adhered  to  ;  seemingly  the  Polistes  approve  of 
the  maxim  that  circumstances  alter  cases.  Many  of 
the  dwellings  are  circular  or  approach  the  round 
(see  Fig.  28),  some  are  as  though  compressed, 
some  oval,  some  simply  composed  of  one  or  two 
long  lines  of  cells,  some  are  eccentric,  forming  at 
first  a  triangle  which  is  finished  with  a  rounded 
end.  The  solid  foundation  of  the  comb  and  the 
strong  slender  pedicle*  that  maintains  it  may  be 
central ;  in  other  cases  it  projects  entirely  from 
one  side  of  the  support  (see  Fig.  29).  The  nests 
never  reach  a  great  size,  often  there  is  only  one  tier  ; 
additional  combs  are  attached  by  pillars  or  foot- stalks 
as  in  Vespa.  The  cells  are  roundish,  and  remarkable 
in  that  their  bases  are  a  trifle  smaller  than  their 
mouths,  a  divergence  hardly  noticeable  in  the  single 
cell,  but  which  produces  a  spreading  outline  when  a 
number  are  massed  together.  Those  in  the  middle 
are  large  and  long,  and  generally  closed,  indicating 
that  the  larvae  are  within,  undergoing  their  transform- 
ations to  perfect  insects.  As  a  rule  the  peripheral 


182          ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

cavities  are  much  shorter,  open  and  empty,  indeed 
one  would  imagine  them  to  be  abortive,  and  too 
small  to  be  of  any  use.  These  are  mere  rudi- 
ments or  outlines,  and  originate  in  a  thrifty  habit 
of  the  wasps  of  constructing  not  only  cells  that 
they  wish  to  fill,  but  of  preparing  others  to  come 
in  handy  by-and-bye.  Within  the  little  cups,  the 
bottoms  of  future  cells,  eggs  can  be  laid,  and  later 
on  the  walls  can  be  lengthened.  These  sketches, 
several  deep,  sometimes  form  a  ring  round  the 
great  cells,  or  comb  properly  so  called.  They  are 
of  advantage  in  permitting  of  rapid  additions  to 
the  nest,  in  a  sense  they  ensure  its  well-being  by 
lessening  the  bad  effects  of  any  shock  or  blow,  and 
they  alone  would  be  flooded  in  the  event  of  pene- 
trating rains.  They  are  less  well  proportioned  than 
the  mediate  cells,  even  the  form  of  the  nest  as  a 
whole  indicates  that  they  are  the  most  oblique,  the 
most  divergent,  and  difficult  to  construct.  Probably 
to  this  cause  must  be  attributed  the  variety  to  which 
the  nests  of  all  kinds  of  Polistes  are  subject.  There 
seems  reason  to  believe  that  the  individuals  bred  in 
the  lateral  apartments  are  neither  so  large  nor  so 
perfect  as  their  kindred  fortunate  enough  to  enter 
the  world  in  the  more  beauteous  central  cradles. 

Polistes  aterrima  forms  its  cells  with  beautiful 
regularity  and  sets  them  in  a  very  peculiar  manner, 
two  deep  on  the  same  horizontal  floor,  and  in  a  couple 
of  pendant  rows.  They  open  downVards,  but  are  not 
quite  perpendicular,  they  incline  a  little  alternately  to 
either  side.  Each  is  placed  rather  lower  than  its 
fejlow,  producing  a  striking  general  effect  and  one 


v  SOCIAL  HOMES  183 

easily  recognisable.  Slight  and  perishable  as  they 
appear,  the  rain  may  fall  in  torrents  without  wetting 
them.  Over  the  whole  the  wasp  lays  a  thick  coating 
of  a  blackish  but  transparent  varnish,  which  renders 
them  waterproof ;  it  also  binds  the  group  firmly 
together,  and  gives  it  a  high  polish.  The  small 
dimensions  of  the  nest  lead  one  to  think  that  these 
wasps  form  societies  of  a  different  nature  from  those 
of  immensely  populous  communities:  Towards  its 
basal  end  the  cells  become  small,  a  diminution  that 
arises  simply  from  the  fact  that  they  are  yet  incom- 
plete ;  originally  the  upper  cells  were  in  the  same 
unfinished  state.  It  is  incorrect,  though  very  natural, 
to  suppose  that  the  higher  and  larger  compartments 
are  for  the  future  males  and  females,  the  lower  and 
smaller  ones  for  the  breeding  of  the  workers.  The 
similarity  of  completed  cells  raises  important  ques- 
tions. Are  these  societies  true  societies,  do  the  males 
and  females  belong  to  the  same  brood,  are  they  of 
like  size,  and  nurtured  in  the  same  cells  ?  Possibly 
the  sexes  are  reared  in  separate  establishments,  on 
the  principle  of  unisexual  or  dioecious*  plants. 

Not  the  least  extraordinary  of  the  wasps  are  the 
Icarias,  a  genus  that  extends  through  most  of  the 
warmer  regions  of  the  world,  specimens  having  been 
taken  in  Africa,  India,  China  and  Australia,  and  in 
many  parts  of  the  Asiatic  Archipelago.  Like  the 
Polistes,  their  nests  are  attached  to  leaves,  stalks,  or 
branches  by  a  single  footstalk,  composed  of  the  same 
papery  material  as  the  cells.  Though  slender  it  is 
hard,  tough  and  solid,  and  the  strength  with  which  it 
is  fastened  to  the  tree  or  plant  is  surprising,  enabling 


184          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

it  to  uphold  considerable  weight.  At  the  end  of  the 
petiole  usually  a  single  cell,  its  mouth  directed  down- 
wards, is  fixed  ;  the  rest  of  the  nest  consists  of  a  double 
series  of  lateral  cells  until  the  group  is  complete. 
Those  nearest  to  the  foot-stalk  are  the  largest  and 
most  perfect,  since  they  are  finished  first;  towards  the 
other  extremity  the  cells  gradually  diminish  in  size, 
and  at  that  point  they  are  only  just  begun.  As  a 
whole  they  are  well-defined  hexagons,  their  colour  is 
often  a  rather  dark  yellowish  brown,  preventing  them 
from  being  conspicuous  in  spite  of  their  curious  pro- 
jection. The  cell-masses  are  small,  so  that  the  societies 
must  be  restricted.  Possibly  each  group  is  the  work 
of  a  single  female,  who  confines  herself  to  raising  her 
own  progeny  which  escape  as  soon  as  they  are  hatched. 
The  nests  are  frequently  numerous  in  the  same  spot, 
and  each  society  may  set  up  a  number  of  separate 
homes  in  the  vicinity  of  one  another.  Perhaps  in  this 
genus,  as  among  the  Polistes,  workers  are  wanting 
(see  Fig.  30). 

The  architecture  of  Apo'ica  may  be  compared  with 
that  of  Polistes.  If  one  were  to  impaste  a  great 
canopy-like  mass  of  cellular  matter  to  the  dorsal  face 
of  a  circular  cell-group  of  Polistes,  then  one  would 
have  a  nest  of  Apo'ica.  The  comb  opens  downwards, 
its  upper  surface  is  convex,  not  that  the  cells  group 
themselves  in  a  cluster  round  a  central  point,  a  mode 
often  giving  birth  to  convexity  of  surface,  the  canopy 
or  ceiling  is  itself  hemispherical,  and  to  its  inferior 
face  the  group  is  attached.  The  cells  are  of  about 
equal  length,  thus  the  thickness  of  the  nest  is  almost 
the  same  throughout,  and  the  undersurface  is  generally 


SOCIAL  HOMES 


185 


more  or  less  concave,  so  that  the  edges  of  the  sphere 
project  and  afford  a  certain  amount  of  protection  to 
the  middle  portion.  The  cellular  canopy  is  a  spongy 
substance,  not  unlike  a  lather  of  soap;  in  reality  it 


FIG.  32. — Wasp's  Nest  (Chartergns  apicalis),  interior  and  exterior. 

is  a  species  of  paper,  and  when  torn  or  cut  offers 
some  resemblance  to  cotton-wool.  It  is  usually  of  a 
yellowish  or  tawny*  colour,  and  somewhat  gummy 
and  glossy.  This  paper  is  kneaded  and  worked  up 
by  the  manufacturers  until  it  becomes  uniform,  and 


1 86          ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

shows  no  trace  of  the  successive  sweeps  of  the  insects' 
jaws,  so  plainly  exhibited  in  the  papery  coverings  of 
the  English  wasps.  The  thick  hemispherical,  cap  is 
varnished  on  the  exterior,  rendering  it  weatherproof ; 
its  use  is  clearly  to  protect  the  bed  of  cells  against 
rain  and  any  body  that  might  strike  them  in  falling 
from  above ;  in  fact  it  takes  the  place  of  a  roof  to  a 
house.  It  likewise  envelopes  the  branch,  or  branches,  to 
which  it  fixes  the  nest,  its  sticky  nature  being  here  of 
great  importance,  and  serves  to  bind  the  comb  firmly 
to  the  plants.  The  cells  are  sometimes  nearly  circular, 
or  deviate  faintly  from  that  form  ;  some  of  them  are 
perfect  hexagons.  It  is  a  most  remarkable  fact  that 
in  the  same  way  though  the  entire  nest-mass  at  times 
is  round,  or  diverges  little  therefrom,  often  it  too  is 
hexagonal,  and  its  six  sides  are  as  regular  and  the 
angles  are  as  true  as  if  they  had  been  drawn  with  rule 
and  compass  (see  Fig.  31).  This  is  commonly  the  case 
with  the  larger  nests  ; — the  great  ones  reach  a  diameter 
of  eleven  or  twelve  inches.  But  near  combs  of  the 
kind  may  be  found  quite  small  hexagonal  specimens, 
showing  that  the  insects  have  started  with  the  idea  of 
constructing  on  these  lines,  and  having  begun  thus 
have  adhered  to  the  conception. 

The  wasps  hitherto  considered  are  distinguished  as 
manufacturers  of  paper,  in  general  fine  and  thin  and 
more  or  less  brittle,  the  weakness  of  which  they 
overcome  by  the  superposition  of  a  great  number 
of  leaves.  There  is  a  large  class  who  while 
they  make  many  kinds  of  papyraceous  tissues,  are 
noted  for  a  feature  in  common — the  fabrication  of  a 
solid  and  tough  paper,  a  veritable  cardboard,  com- 


v  SOCIAL  HOMES  187 

posed  of  only  one  layer  of  material,  at  times  very 
thick  and  resisting,  at  others  slight  and  supple.  Of 
this  substance,  after  the  manner  of  Vespa,  the  wasps 
usually  build  a  papyraceous  envelope  or  sac  for  the 
inclosure  of  their  combs,  and  as  in  that  genus,*  the 
covering  follows  closely  the  direction  of  the  plan  of 
the  cells.  These  nests  attain  an  extraordinary  degree 
of  development  and  house  a  vast  multitude  of  in- 
dividuals; even  our  nests  of  Vespa,  the  best  suited  of 
the  previous  category  to  support  large  populations, 
are  extremely  limited  compared  with  some  of  the 
societies  in  question.  The  cause  of  the  excessive  in- 
crease is  unknown,  whether  it  be  that  these  societies 
are  formed  on  other  bases,  or  that  the  climates  that 
give  them  birth  do  not  impose  such  stringent  peri- 
odic destruction  upon  them  as  our  winter  season 
does  upon  those  at  home.  Exposure  to  the  more 
favourable  climatic  conditions,  however,  does  not  lead 
to  great  increment  among  Vespa  and  Polistes  ;  many 
of  these  companies  abroad  can  hardly  be  said  to  be 
less  scanty  than  ours,  and  it  seems  not  unreasonable 
to  conclude  that  a  distinct  difference  lies  at  the  root 
of  the  economy  of  the  two  classes. 

The  genus  Chartergus,  one  of  the  important 
groups  of  the  cardboard  makers,  includes  insects 
apparently  similar  which  practise  two  strangely 
different  forms  of  nidification.  The  nests  of  C. 
chartarius,  the  most  common  in  collections,  are  of 
frequent  occurrence  in  tropical  America.  Their  card- 
board is  white,  gray,  or  of  a  buff  colour,  tending  to 
yellow,  very  fine  and  of  polished  smoothness  ;  at  the 
same  time  it  is  strong  and  so  solid  as  to  be  imper- 


188          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

vious  to  the  weather.  It  cannot  be  urged  sufficiently, 
says  Reaumur,  that  this  kind  of  envelope  is  indeed  of 
a  veritable  cardboard,  as  beautiful  as  any  we  know 
how  to  make.  Reaumur  once  showed  a  piece  to  a 
cardboard  manufacturer,  and  not  the  slightest  sus- 
picion of  its  real  nature  was  suggested  to  his  mind. 
He  turned  it  over  and  over,  he  examined  it  thoroughly 
by  the  touch,  he  tore  it,  and  after  all  declared  it  to 
be  made  by  one  of  his  own  profession,  mentioning 
manufacturers  at  Orleans  as  the  probable  producers. 
The  nests  may  be  conical  or  cylindrical,  they  may 
be  straight  but  more  often  are  somewhat  curved,  some 
are  almost  globe-shaped,  but  these  varieties  are  of 
little  importance.  The  length  of  a  well-sized  nest  is 
about  a  foot ;  the  largest  yet  discovered  was  in  Ceylon, 
and  measured  the  astonishing  size  of  six  feet.  The 
edifice  is  pendulous  on  trees,  and  attached  as  it  were 
to  a  suspensory  ring,  which  embraces  the  branch,  and 
is  tightly  impasted  round  it,  or  according  to  West- 
wood  may  be  large  compared  with  the  latter's  circum- 
ference, but  it  is  probably  a  mistake  to  say  that  the 
nest  ever  swings  freely  as  on  a  pivot.  The  interior 
consists  of  circular  concave  horizontal  platforms  of 
cells,  their  mouths  turned  downwards,  each  tier 
stretching  right  across  like  so  many  floors,  and 
fastened  along  its  entire  edge  to  .the  walls.  Com- 
munication is  effected  by  a  central  opening  through 
the  bottom,  and  through  every  tier.  When  the 
number  of  inhabitants  becomes  very  great  and  a 
fresh  series  of  cells  is  added,  unlike  the  British  wasps 
who  add  to  their  abodes  by  a  preliminary  increase  of 
the  envelope  to  admit  of  extension  of  the  tiers, 


v  SOCIAL  HOMES  189 

the  Chartergus  go  to  work  on  precisely  the  opposite 
plan,  first  forming  new  cells  and  covering  them  after- 
wards. Taking  the  bottom  of  the  nest  as  starting- 
point  they  set  cells  over  its  exterior  surface, 
being  careful  to  extend  the  circumference  by  a  row 
or  two  to  augment  the  diameter  in  proportion  to  the 
length,  so  that  the  symmetry  of  the  building  may  not 
be  lost.  The  walls  are  then  lengthened  to  include 
the  fresh  stage,  and  the  end  is  closed  with  a  new  floor, 
in  its  turn  to  become  the  ceiling  of  the  next  tier  of 
cells  when  further  enlargement  is  desired.  No  trace 
of  the  addition  is  visible  on  the  outside  of  the 
envelope,  which  would  seem  constructed  at  one 
stroke. 

The  nest  of  C.  apicalis  is  uneclipsed  for  grace  of 
design  ;  it  is  one  of  the  most  wonderful  examples  of 
intelligent  workmanship  among  insects.  Exteriorly 
the  form  is  a  more  or  less  fusiform*  or  spindle-shaped 
sac,  terminating  at  its  inferior  extremity  in  a  prolong- 
ation or  narrow  neck,  which  is  open  and  constitutes 
the  entrance.  The  sac  surrounds  and  impastes  the 
branches  of  trees,  which  piercing  it  almost  from  end 
to  end  act  as  its  support.  To  the  branches,  in  the 
interior  a  number  of  combs,  one  above  the  other  much 
as  in  Vespa,  are  affixed  ;  as  a  rule  the  largest  and 
straightest  among  them  becomes  the  axis  to  the 
whole  edifice.  When  the  axes  are  multiplied,  the 
regularity  of  disposition  of  the  combs  is  destroyed  ; 
numerous  small  cell-groups  are  commenced  on  the 
different  branches,  and  at  different  levels,  and  do  not 
unite  to  form  perfect  and  complete  tiers.  Due  to  the 
shape  of  the  spindle,  the  higher  and  lower  combs  are 


I9b         ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

the  smallest,  the  least  mature,  so  to  speak  ;  the  middle 
ones  are  given  ample  room  in  the  inclosure,  and  may 
be  increased  to  great  size.  While  the  former  are 
simply  fixed  against  the  axis  and  are  more  or  less 
spreading,  the  larger  tiers  tend  to  surround  it  on  all 
sides,  so  that  the  axis  penetrates  through  them, 
though  always  somewhat  excentrically.  Communi- 
cation between  the  terraces  is  by  spaces  on  the  inner 
side  of  the  covering,  a  simple  sheet  of  paper,  which, 
though  slight,  is  solid  and  well  gummed.  Its  surface  is 
irregularly  indented ;  sometimes  wrinkled  transversely 
and  circularly,  and  with  great  exactness.  In  some 
nests,  on  one  or  other  of  the  faces,  the  points  where 
the  zones  of  paper  and  the  wrinkles  meet  are  very 
plainly  shown,  making  the  spindle  look  as  though  it 
were  goffered.  The  branch  that  is  accounted  the 
true  axis  is  never  vertical;  a  slanting  one  is  chosen  as 
affording  greater  support.  The  neck  projects  to  one 
side,  and  consequently  it  becomes  necessary  if  the 
combs  are  to  retain  a  horizontal  position,  that  they 
cut  the  stem  at  an  oblique  angle. 

Notwithstanding  the  sustaining  power  of  the  axis, 
the  tiers  stand  greatly  in  need  of  certain  accessory 
though  irregular  props.  Frequently  they  are  united 
by  pedicels,  or  columns,  and  are  affixed  to  the  interior 
of  the  covering  by  their  edges  by  little  scales  or 
sheets  of  paper,  leaving  holes  to  enable  the  wasps  to 
get  from  story  to  story.  In  this  manner  they 
are  kept  in  their  place,  and  the  covering  itself  is 
rendered  stronger  by  its  numerous  points  of  union 
with  other  substances.  Another  important  means 
of  support  is  gained  by  arched  strips  of  paper 


v  SOCIAL  HOMES  191 

adherent  to  the  envelope,  and  more  or  less  per- 
pendicular to  it,  which  traverse  the  inner  space  and 
unite  the  borders  of  the  combs,  forming  as  it  were 
vertical  partitions  upon  the  interior  circumference  of 
the  sac.  Enlargement  of  the  nest  is  effected  as  in 
Vespa,  but  with  greater  difficulty,  since  the  envelope 
is  composed  of  a  single  leaf.  Great  cell-like  papery 
protuberances  are  raised  on  its  surface,  and  subse- 
quently the  portions  covered  are  eaten  away  by  the 
builders  from  the  inside.  The  pedicels,  or  columns, 
above  mentioned,  which  unite  the  combs  to  each  other, 
arise  from  careful  preservation  of  parts  of  the  old 
mantle,  which  naturally  extend  from  the  border  of 
comb  to  comb.  In  the  same  way  the  vertical  sheets 
of  paper  alluded  to,  which  bind  the  combs  to  the  new 
portion  of  the  envelope,  originate  in  the  retention  of 
the  old  leaf  throughout  its  lines  of  meeting  with  the 
fresh  superimposed  coat ;  and  when  the  combs  are 
extended  to  reach  that  coat,  the  strips  form  the  par- 
titions described  upon  the  circumference  of  the  tiers 
adding  much  to  their  solidity.  In  spite  of  all  these 
clever  precautions  the  nest,  owing  to  the  feeble 
character  of  the  envelope,  is  one  of  extreme  fragility. 
The  other  kind  of  nest  of  Chartergus  is  con- 
structed on  a  straight  and  upright  branch,  having  no 
lateral  twigs.  Its  elegance  cannot  be  sufficiently  ad- 
mired. Composed  of  a  few  cells  only,  the  combs 
are  attached  to  the  branch  by  means  of  petioles, 
or  solid  masses  of  wax,  keeping  the  groups  in  a 
horizontal  and  parallel  position.  They  stand  one 
over  the  other,  sometimes  to  the  number  of  ten,  separ- 
ated by  considerable  intervals,  and  so  admirably 


192          ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

upheld  by  the  petioles  that  the  aid  of  all  pillars 
or  columns  is  dispensed  with.  The  envelope  is 
a  spindle  of  a  single  leaf  of  ligneous*  paper,  most 
artistic  in  appearance,  being  marked  with  transverse 
parallel  tubings  and  goffered.  The  fibres  of  the 
tissue  are  arranged  with  surprising  regularity;  all 
the  zones  are  united  with  consummate  art,  and  meet 
in  a  long  and  plainly  shown  line ;  the  paper  may  be 
also  variegated  with  longitudinal  bands  of  different 
colours.  The  vase  is  firmly  affixed  to  its  axis  at 
points  slightly  above  and  below  the  uppermost  and 
lowermost  combs,  at  no  part  is  it  in  continuity 
with  the  combs,  there  is  plenty  of  space  between  the 
two  fabrics  for  the  wasps  to  pass  up  and  down  within 
their  home  with  ease.  Taking  advantage  of  the 
wholly  lateral*  position  of  the  combs  with  respect  to 
the  axis,  the  wasps  render  their  building  less  fragile 
than  it  would  otherwise  have  been  by  placing  the 
branch  to  one  side  of  the  spindle,  and  it  saves  time 
and  trouble,  without  materially  impairing  the  sup- 
port, to  leave  the  wood  exposed  at  the  posterior 
surface  of  the  papery  mass.  The  opening  is  small  and 
situated  at  the  lower  end  (see  Fig.  32). 

The  pensile  nest  of  Tatua  morio  bears  great  external 
resemblance  to  the  ^pendulous  cone-shaped  nest  of 
Chartergus  chartarius,  and  is  common  in  the  same 
country.  Two  remarkably  good  specimens  may  be 
seen  in  our  national  collection.  The  outer  walls  are 
of  a  solid  and  durable  paper,  which  is  likewise  thick, 
hard,  smooth,  and  of  a  dark  brown.  Storms,  however 
fierce,  have  little  ill-effect  on  homes  so  well  protected. 
Hardly  less  thick  and  strong  are  the  various  cell-floors, 


v  SOCIAL  HOMES  193 

like  the  floors  of  the  Chartergus  circular  in  plan, 
but  flat,  and  the  union  of  each  with  the  envelope 
is  absolutely  perfect.  The  entrance,  however,  is  en- 
tirely lateral,  and  the  insects  gain  admission  to  the 
different  tiers  by  very  eccentric*  holes.  A  nest  well 
in  progress  contains  many  combs.  In  one  of  the 
kind  the  lower  chambers  are  likely  to  be  incom- 
plete, since  the  floors  are  made  before  the  cells  are 
built.  The  wasps  seem  always  to  be  in  readiness 
for  an  emergency ;  they  build  new  stages  ere  they 
require  them,  and  lay  the  foundations  of  future  cells. 
The  construction  of  the  former  is  a  long  and  toilsome 
business,  but  the  latter  are  quickly  formed,  and 
eggs  can  be  laid  in  cells  that  are  just  begun  ;  during 
the  development  of  the  larvae  there  is  abundance 
of  time  to  finish  them.  How  many  tiers  are  made 
before  cells  are  attached  to  them,  or  whether  cells  are 
added  as  soon  as  the  floors  are  completed  are  at 
present  moot  points.  Though  at  the  beginning  of 
winter  the  nests  are  abandoned,  they  long  resist  the 
severity  of  the  season  ;  whether  the  societies  are  dis- 
solved every  year  has  not  been  ascertained.  It  is 
equally  uncertain  if  colonies  take  possession  of  desert- 
ed nests  or  invariably  build  anew.  Each  comb  may 
serve  for  one  laying,  or  may  be  cleansed  and  put  to 
further  use. 

The  genus  Polybia  is  common  in  tropical  America, 
in  the  Asiatic  Archipelago  it  occurs  more  sparingly 
but  is  unknown  in  Europe.  Some  of  the  small  homes, 
as  those  of  P.  palmarum  and  sedula,  generally  consist 
of  a  single  comb  of  hexagonal  cells  on  the  surface  of 
a  leaf,  and  clothed  with  a  ceiling  of  somewhat  frail 

O 


194 


ROMANCE  OF  THE  INSECT  WORLD      CHAP. 


paper,  with  an  aperture  towards  the  lower  end. 
The  insects  have  the  sagacity  to  fix  them  to 
the  underside  of  the  leaf,  so  as  to  cause  it  to 
bend  and  form  a  natural  roof.  The  building  is  also 


FIG.  33. — View  of  exterior  of  nest  of  Myrapetra  scutellaris. 

made  to  follow  the  shape  of  the  supporting  foliage, 
being  round  or  oval  under  large  broad  leaves,  long  and 
slender  under  linear*  leaves,  and  its  size  is  always 
carefully  limited,  so  that  the  leaf  projects  on  all  sides. 
When  the  comb  is  full  it  appears  that  a  second  stage 


SOCIAL  HOMES 


195 


may  be  added  upon  the  cover,  and  is  completed  with 
an  envelope  or  ceiling.  The  regularity  and  perfection 
of  construction  is  wonderful. 

P.  liliacea  makes  a  marvellous  and  often  gigantic 


FIG.  34. — View  of  interior  of  nest  of  Myrapetra,  scutellaris. 

nest,  four  to  five  feet  long,  and  of  a  diameter  of  one  or 
two  feet,  containing  thousands  of  cells.  It  is  sus- 
pended from  the  branches  of  trees  ;  its  covering  is  a 
rough  cardboard,  sometimes  of  a  red-brown  ;  it  is 
compressed  at  the  top  but  widens  out  towards  the 

O  2 


196          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

base.  P.  rejecta  ofttimes  forms  a  cone-shaped  pend- 
ant nest,  which  when  increased  to  great  extent  ends 
in  a  long  symmetrical  cylinder.  Other  nests  are 
flask-shaped,  the  base  being  fastened  to  the  tree ; 
some  are  almost  globular.  The  species  to  whom  the 
last  belong,  carrying  out  still  farther  the  principle  of 
enlargement  adopted  by  CJiartergus  chartarius  and 
Tatua,  build  by  placing  cells  not  merely  upon  the 
outer  surface  of  the  layer  of  cardboard  which  at  the 
moment  constitutes  the  bottom  of  the  nest,  the  entire 
outer  wall  is  covered  with  cells,  when  the  fresh  tier  is 
closed  in  with  a  new  envelope.  Thus  a  fairly  large 
nest  is  composed  of  a  whole  series  of  concentric 
combs,  forming  hollow  spheres  set  one  within  the 
other,  not  unlike  the  well-known  ivory  puzzle  balls  of 
the  Chinese,  the  papery  ceiling  of  each  comb  having 
been  originally  the  outer  wall  of  the  nest.  It  follows 
from  this  arrangement  that  the  direction  of  the  cells 
is  not  uniform,  as  is  generally  the  case  with  social 
Hymenoptera.  They  are  neither  all  placed  vertically 
with  their  mouths  downwards,  like  those  of  most 
wasps,  nor  are  they  horizontal,  as  made  by  the  bee. 
On  the  contrary,  their  bases  all  point  towards  the 
centre  of  the  nest,  and  all  their  mouths  radiate 
outwards.  The  various  comb-tiers  are  generally 
remarkably  close,  and  pierced  with  holes  for  com- 
munication. 

Very  extraordinary  are  some  of  the  nests  be- 
longing to  this  genus  in  the  collection  of  the 
British  Museum — the  works  of  Myrapetra  scutellaris 
(see  Fig.  33),  a  mere  fanciful  title.  These  huge  erec- 
tions are  from  Central  America,  and  the  native  authori- 


v  SOCIAL  HOMES  197 

ties  say  of  one  that  it  is  not  composed  of  wood  fibres, 
but  of  the  dung  of  the  Capincha,  one  of  the  aquatic 
cavies  of  the  region.  One's  attention  is  instantly 
attracted  to  the  fairly  conical  knobs  or  tubercles*  with 
which  the  surface  is  thickly  beset,  of  various  size,  and 
most  pointed  where  they  are  least  exposed.  Their 
disposition  is  in  horizontal  zones,  seeming  to  corre- 
spond more  or  less  with  the  comb-tiers.  While  at  the 
top  of  the  nest  they  are  comparatively  few,  gradually 
the  numbers  increase  towards  the  lower  end,  and  on 
the  bottom  they  are  so  numerous  that  one's  finger  can 
scarcely  be  laid  between  them.  Like  the  envelope 
they  are  made  up  of  several  papery  layers  so  closely 
blended  as  to  be  hardly  distinguishable,  forming  a  sub- 
stance astonishingly  thick,  hard,  and  firm,  in  colour 
of  a  dull  dark  brown,  and  of  very  coarse  texture. 
Of  what  use  they  are  it  is  difficult  to  decide  ; 
they  may  be  simply  freaks  of  nature.  Although 
their  tips  are  not  acute,  they  may  defend  the  abode 
against  the  attacks  of  tigers,  jaguars,  kuguars,  and 
other  mammalia  partial  to  honey  and  the  grubs  of  the 
hive.  The  nest  always  hangs  low,  seldom  more  than 
three  or  four  feet  from  the  ground,  and  protection 
would  appear  much  needed.  It  seems  hardly  possible 
to  deny  that  they  are  for  the  double  purpose 
of  concealing  and  of  sheltering  the  entrances, 
which  are  invisible  when  the  nest  is  looked  at 
from  above.  Examination  reveals  them  beneath  a 
row  of  the  projections,  which  overhang  them  and 
keep  off*  the  rains  like  the  eaves  of  a  house  ;  the 
passages  are  also  intricately  twisted,  so  as  to  prevent 
the  ingress  of  moths  or  other  enemies  of  any  size.  It 


198          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

is  strange  that  the  inferior  surface  of  the  nest  is  pro- 
vided with  tubercles,  a  circumstance  that  must  put  the 
insects  to  the  trouble  of  gnawing  them  away  each 
time  they  add  a  stage.  Probably  the  same  material 
is  again  employed  in  establishing  fresh  cells,  and  in 
building  the  new  platform. 

A  longitudinal  section  shows  the  peculiar  disposi- 
tion of  the  combs.  Just  as  in  the  spherical  nests  of 
Polybia,  the  highest  ones  are  perfect,  or  almost 
perfect,  spheres;  but  this  method  of  construction  is 
soon  found  to  be  too  laborious.  A  nearly  globular 
mass  of  the  brown  paper-like  substance  exists  at  the 
top,  the  nucleus  so  to  speak.  The  first  combs  closely 
surround  this,  so  that  they  form  the  best  parts  of  hollow 
spheres,  then  come  great  arcs  of  circles,  followed  in 
regular  order  by  other  tiers,  their  rotundity  becoming 
gradually  reduced  until  the  curve  of  the  lower  ones  is 
extremely  shallow,  exactly  like  the  tiers  of  Tatua, 
except  that  they  exhibit  a  trifling  convexity  on  their 
lower  surfaces.  They  are  carried  to  the  common 
wall,  and  thereto  affixed,  small  spaces  being  left  open 
here  and  *here  between  their  edges  and  the  envelope. 
The  solid  wall  at  the  top  is  of  great  thickness  (see 

Fig.  34)- 

In  the  nest  in  the  British  Museum  already  described, 
a  quantity  of  brownish-red  honey  was  found  in  the 
upper  combs,  but  hard  and  dry.  Even  so  long  ago 
as  the  beginning  of  the  century,  Azara,  a  Spanish 
officer,  who  was  sent  out  by  his  government  to 
Paraguay  to  make  certain  investigations  in  that 
country,  mentions  that  a  South  American  wasp  which 
he  calls  Chiguana  has  the  strange  habit  of  hoarding 


v  SOCIAL  HOMES  199 

honey.  The  Chiguana  of  Azara,  it  would  seem,  is 
identical  with  Polybia  scutellaris.  At  the  time  of 
publication  Azara's  statement  was  not  believed,  so 
opposed  was  the  habit  that  he  claimed  for  this  insect 
to  the  known  actions  of  wasps.  He  and  his  men  ate 
from  the  Chiguana's  store,  and  it  proved  deleterious. 
St.  Hilaire,  a  subsequent  traveller,  speaks  of  two 
South  American  honey-wasps.  The  honey  of  one 
was  white  and  innocuous,  that  qf  the  other  was  reddish- 
brown  and  poisonous.  The  good  honey  was  in  an 
oval  light-coloured  nest,  of  thin  papery  material, 
totally  different  from  the  paper  of  Myrapetra,  and 
was  observed  by  Hilaire  on  a  small  bush  near 
Uruguay,  at  a  distance  of  only  about  a  foot  from  the 
ground.  This  wasp  has  been  described  as  Lecheguana. 
Probably  under  the  term  Lecheguana,  or  Chiguana  as 
Azara  has  it,  the  inhabitants  of  America  confound 
many  wasps  of  similar  kinds,  and  it  is  rather  a 
generic  title  for  all  honey  wasps  than  for  one  species 
in  particular. 

That  honey  is  contained  in  these  nests  there  can  be 
no  question  ;  the  fact  is  proved  beyond  doubt  by 
those  in  the  British  Museum.  At  the  same  time  it  is 
evident  that  the  papery  material  is  extremely  ill- 
suited  for  the  retention  of  the  liquid,  which  has  pene- 
trated and  dropped  from  layer  to  layer  of  comb  and 
materially  damaged  the  cells.  A  nest  of  P.  scutellaris 
containing  honey  was  presented  to  the  Museum  about 
thirty  years  ago.  In  no  part  of  it  were  brood,  nor 
did  it  appear  to  have  been  recently  in  use  for  the 
purpose  of  hatching.  Can  it  be  possible  that  it  was  a 
deserted  nest,  adopted  by  a  society  of  wasps  merely 


200          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

as  a  temporary  receptacle,  a  magazine  for  booty  ? 
Wasps  are  well  known  to  plunder  hives,  and  the 
honey  may  have  been  treasure  stolen  from  the 
stores  of  some  Melipona  or  Trigona  bee.  If 
Polybia  are  really  makers  of  honey,  it  seems  only 
reasonable  to  expect  that  their  cells  would  be  of  a 
nature  to  contain  it ;  moreover,  that  the  stock  laid  by 
would  constitute  food  for  the  young  as  well  as  for 
the  community  at  large.  It  must  be  admitted  that  the 
absence  of  brood  may  be  explained  by  the  suppo- 
sition that  the  collection  is  made  in  the  off-breeding 
season,  when  the  company  would  consist  solely  of 
adults  ;  and  when  the  death  or  repose  of  natural  life 
precludes  the  wasps  from  gathering  food  abroad,  the 
honey  would  serve  them  in  good  stead.  The  idea 
has  been  started,  but  merits  little  credence,  that  a 
nest  of  this  kind  is  a  forsaken  wasps'  nest  invaded 
by  some  species  of  Trigona  bee.  Wasps'  cells  are 
unadapted  to  the  great  pursuit  of  bees,  besides  being 
considerably  too  large  for  the  proper  accommodation 
of  these  bees'  larvae. 

The  Nectarinia  are  likewise  believed  to  be  collectors 
of  honey.  Their  beautiful  globular  nests,  of  fine  grey 
paper  like  the  paper  of  Vespa,  but  made  up  of  a 
single  layer,  are  plentiful  in  the  deep  recesses  of  the 
Brazilian  and  Mexican  forests,  being  suspended  near 
the  ground  from  the  boughs  of  bushes,  while  long 
delicate  leaves  and  branches  are  woven  into  their 
substance,  and  in  many  places  are  carried  through 
it  and  project  on  the  other  side.  As  in  the 
case  of  Myrapetra,  they  consist  of  series  of 
tiers  composed  alternately  of  comb  and  cover,  the 


v  SOCIAL  HOMES  201 

last    being   the    leafy   envelope.      The    spheres    are 
more  perfect  than  those  of  Myrapetra,  but  they  are 
not  always  literally  concentric*  circles,  and  in  reality 
they  are  incomplete  towards  the  summit  of  the  nest. 
This    irregularity  is  unavoidable,    for  if    the   combs 
were  only  united  at  the  top  they  could  not  be  kept 
fixed  firmly  in  their  relative  positions  ;  no  pillars  of 
union  between  them  exist,  as  in  Vespa.     Nature  sub- 
stitutes an  excellent  contrivance,  which  is  at  once  a 
means  of  communication  and  a  prop  to  the  edifice. 
A  veritable  flight  of  stairs  extends  throughout  the 
nest   from    the   centre   to   the    lower   surface.      The 
Nectarines,    like     other    cardboard     wasps,     pierce 
holes   through    their  successive  stages   as    a   means 
of  traffic  ;    the    combs  being    of  immense    breadth, 
the   holes    are  numerous  to   save   time   and  fatigue 
in    gaining    the    exits,    and    the    overcrowding     of 
the    passages    that    would    otherwise    result    in    the 
populous     communities.       But     these      routes      are 
not    deemed    adequate    for    comfort    and    conveni- 
ence.    To    the   underside   of  the   great   orifice  with 
which  each  comb-tier  is  perforated,  material  is  added, 
and  prolonged  obliquely  downwards,  so  as  to  meet 
the  platform  of  the  comb  lower.     Tier  after  tier,  from 
the  top  to  the  bottom  of  the  nest,  bears  the  same 
arrangement ;  the  hole  in  each  tier  is  situated  below 
that  of  its  immediate  predecessor.      It  will  be  per- 
ceived that  the  wasps  in  descending  or  ascending  by 
these  stairs  and  through  these  holes,  pass  in  spiral* 
fashion  from  the  centre  to  the  circumference  of  the 
nest.     The  envelope  itself  is  penetrated  with  a  hole, 
and    the  ladder  leads  out  into  the  open  air.     These 


202          ROMANCE  OF  THE  INSECT  WORLD       CH.  v 

communicating  sheets  have  other  uses.  Determined 
to  make  the  most  of  everything,  the  industrious  wasps 
cover  the  undersides  of  the  papery  plates  with  cells. 
They  are  therefore  comb-ceilings,  as  well  as  staircases 
and  pillars.  Without  going  into  details,  the  domain 
may  be  said  to  be  enlarged  by  an  extra  sphere  of  cells 
upon  the  outside  of  the  envelope  and  a  fresh  coat  of 
paper. 

If  the  outer  surface  of  a  nest  were  covered  with  cells 
it  would  hold  some  thousands.  Since  the  interior  is 
made  up  of  numerous  similar  surfaces,  little  smaller, 
one  can  hardly  compute  the  sum  total  of  inhabitants 
possible  to  be  contained  in  such  a  city.  Of  all  the 
kinds  of  wasps'  nests,  this  of  the  Nectarines  is  the 
best  for  holding  a  large  community.  Due  to  its 
sphericity,  the  cells  find  room  with  the  least  expendi- 
ture of  material.  And  while  it  can  exceed  others  in 
cell  capacity,  and  consequently  in  population,  in 
actual  volume  it  is  far  less  cumbersome  than  other 
great  nests. 


CHAPTER  VI 

DEFENCES  OF  INSECTS,  OR  PROTECTION  AS  DERIVED 
FROM  COLOUR 

Need  of  insects  of  means  of  defence — Adaptation  of  their  exter- 
nal colouring  to  conditions  of  life — Protective  Resemblances 
— herein  find  explanation  of  first  and  most  widespread  use 
of  colour  among  animals — Principle  of  adaptive  colouring 
solved  by  theory  of  natural  selection — Commonness  of 
general  harmony  between  colouring  of  insects  and  tints  of 
nature — Imitative  tints  of  undersides  of  wings  of  butterflies 
— Special  Protective  Resemblance — 'stick-caterpillars 'and 
others — leaf-butterflies — British  and  European  moths — 
among  Orthoptera — tropical  "  walking-leaf"  and  "  walking- 
stick  "  insects — other  insects  and  spiders — Alluring  colour- 
ing— Resemblance  of  Mantises  and  spiders  to  flowers — to 
excreta  of  birds — Changes  of  colour  corresponding  to 
changes  of  environment — Di-  and  Polymorphism — their 
value — meaning  obscure — Variable  Protective  Resemblance 
in  pupae — in  larvae — in  colours  of  cocoons — in  perfect 
insects — Variable  Protective  Resemblance  and  the  origin 
of  colour — Power  of  adjustment  of  colour  is  adaptive,  and 
is  produced  and  maintained  by  natural  selection. 

IT  is  unnecessary  to  enlarge  upon  an  insect's  need  of 
means  of  defence.  Obviously  no  creature  could  be 
more  open  to  attack,  and  added  to  its  peculiarly 
defenceless  condition  on  all  hands  innumerable 


204          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

enemies  wage  continual  war,  many  of  whom  derive 
their  whole  sustenance  from  insects.  Nor  are  these 
tribes  at  peace  with  their  own  kind,  but  ever  live  in  a 
state  of  internecine  broil,  the  strong  often  preying  on 
the  weak  and  the  cunning  upon  those  of  simpler  wit. 
An  insect  is  like  a  country  of  diminutive  size,  and 
apparently  almost  wanting  in  natural  safeguards. 
No  seas  of  unrivalled  swiftness  of  motion  roll  round 
it  and  shield  it  from  the  depredations  of  foes  ;  no 
mountain  barriers  of  strength  enable  it  to  withstand 
them.  But  our  insect  world  is  not  without  resource. 
Though  small,  its  inhabitants  are  in  multitude  infinite  ; 
and  though  from  their  nature  seldom  able  to  flee  or  to 
fight,  on  them  are  bestowed  different  modes  of  resist- 
ance to  fate  to  save  the  race  from  extirpation. 

Among  biological  phenomena  of  great  interest,  the 
principle  of  disguise  has  long  been  known  to  exist  in 
most  classes  of  the  animal  kingdom.  In  other,  per- 
haps plainer,  words,  their  external  colouring  is  adapted 
to  their  conditions  of  life.  The  resemblances  are  of 
different  kinds;  the  most  usual  are  cases  of  simple 
concealment.  The  animal  in  form  as  in  colour 
imitates  or  simulates,  more  or  less  exactly,  the  ap- 
pearance of  some  object  in  its  environment  which  is 
of  no  interest  to  its  enemies,  and  thus  passes  un- 
detected ;  or  it  harmonises  in  a  general  way  with  its 
surroundings,  and  so  succeeds  in  eluding  attention. 
In  these  instances  the  object  imitated  is  invariably 
inanimate  or  part  of  a  vegetable  structure.  The  analo- 
gies go  by  the  name  of  "  protective  resemblances." 

It  does  not  seem  possible  for  an  insect  to  be  more 
simply  and  admirably  defended  than  by  this  system. 


vi  DEFENCES  OF  INSECTS  205 

More  or  less  complete,  concealment  is  useful  to  many 
animals,  but  to  insects  it  is  absolutely  essential,  and 
accordingly  in  insects  adaptation  to  environment  is 
most  fully  and  markedly  developed.  In  the  animal 
world  the  members  eat  as  they  are  eaten.  To  those 
that  live  upon  others,  and  to  whom  activity  and 
energy  are  denied,  compensation  in  the  boon  of  colour 
is  also  important — colour  such  as  may  best  serve  the 
possessor  to  avoid  alarming  its  prey,  either  by  its 
presence  or  its  approach.  That  in  this  explanation 
is  learned  what  is  the  first  and  most  widespread  use  of 
colour  among  animals  seems  corroborated  by  the  fact, 
that  protective  resemblance  is  apparently  possessed 
by  insects  in  proportion  to  their  sluggish  movements 
or  absence  of  other  means  of  defence. 

This  principle  of  adaptive  colouring,  though  early 
recognised,  found  no  intelligible  exposition  until  the 
year  1859,  when  it  met  with  perfect  satisfying  solution 
in  Darwin's  theory  of  natural  selection,  by  which  he 
explains  how  it  was  that  evolution  took  place. 
Formerly  among  a  certain  section  of  the  community 
the  problem  was  referred  to  an  originally  created 
specific  peculiarity,  or  the  adaptation  was  understood 
to  be  due  to  the  direct  action  of  climate,  food,  or  soil. 
But  while  the  former  interpretation  puts  an  effectual 
bar  to  reasonable  inquiry,  since  we  cannot  get  beyond 
the  fact  of  the  adaptation,  the  second  was  found  to  be 
far  from  adequate  to  cope  with  all  the  varied  phases 
of  this  strange  phenomenon,  and  was  controverted 
by  some  well-known  facts.  The  gradually  increasing 
change  of  disguised  species,  from  a  general  harmony 
with  surroundings  to  precise  imitation  of  particular 


206  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

objects,  is  rather  to  be  accounted  for  by  the  laws  of  a 
struggle  for  existence  and  survival  of  the  fittest,  while 
the  elements  permitting  the  birth  and  progress  of  the 
resemblance  exist  in  the  individual  variability  of  the 
species,  a  variability  that  is  hereditary. 

The  commonness  of  the  occurrence  of  a  general 
resemblance  or  harmony  of  colouring  between  insects 
and  the  prevailing  tints  of  nature,  a  similarity  in 
general  artistic  effect,  is  hardly  conceived  by  those 
unaccustomed  to  watch  or  speculate  upon  such  things 
as  these.  In  the  different  tribes,  in  the  most  adverse 
orders,  this  kind  of  protection  abounds,  affording  its 
several  possessors  greater  or  less  degree  of  invisibility 
to  the  prying  eyes  of  antagonists,  or  the  fear-fraught 
glance  of  the  wished-for  prey. 

In  the  tropics  the  colours  of  thousands  of  species, 
though  perhaps  brilliant  and  far  from  being  alike,  blend 
completely  with  the  aspect  of  the  spots  where  the 
insects  habitually  repose.  At  a  few  feet  distant  the 
surface  and  the  insect  may  be  absolutely  indistinguish- 
able. It  is  one  thing  to  see  an  insect  by  itself  in  a 
collector's  cabinet,  quite  another  matter  to  witness  it 
in  the  state  in  which  it  ordinarily  exists.  Seen  apart 
from  its  surroundings  it  may  appear  bright,  and  not 
adapted  to  escape  observation ;  in  its  everyday  haunts, 
probably,  that  very  brilliancy  enhances  its  conceal- 
ment. The  truth  is  we  fail  adequately  to  appreciate 
the  tones  of  inanimate  nature.  We  make  little  or 
no  allowance  for  the  infinite  complications  wrought 
by  the  ceaselessly  changing  play  of  light  and  shade 
upon  colours  which  in  themselves  are  far  from  uniform. 
A  gaudy  insect  with  numerous  hues,  if  viewed  in  con- 


VI 


DEFENCES  OF  INSECTS 


207 


nection  with  its  surroundings,  or  at  a  distance,  may 
match  neighbouring  objects,  and  be  lost  as  it  were,  or 
at  least  may  obtrude  itself  less  than  if  uni-coloured,  or 


FIG.  35. — A  "Stick-caterpillar"   (Ennomos  tiliaria),   which  in  colour,  form,   and 
attitude  closely  resembles  a  twig  of  a  tree  upon  which  it  lives. 

adorned  with  tints  more  feebly  contrasted.  For  this 
reason  many  tropical  insects  that  take  diurnal  rest 
clinging  to  the  bark  of  dead  or  fallen  trees  are  not 
wholly  brown  ;  the  brown  is  delicately  mottled  with 


208          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

gray,  the  disposition  of  the  two  colours  being  sym- 
metrical and  in  endless  variety  of  design.  Nearer 
home,  to  take  a  familiar  example,  the  large  and  com- 
mon caterpillar  of  the  Privet  Hawk  Moth  {Sphinx 
ligustri)  is  in  reality  striking  in  its  green  dress  and 
purple  stripes.  But  although  it  looks  so  conspicuous 
it  harmonises  remarkably  well  with  its  food-plant, 
and  is  sometimes  troublesome  to  find.  The  purple, 
a  dangerous  introduction  of  colour  one  might  be  led 
to  suppose,  tends  to  neutralise  the  vivid  effect  of  the 
extensive  green  area. 

However,  deception  of  assailants  or  assistance  in 
capture  is  often  obtained  by  the  reproduction  with 
great  exactness  of  the  colour  of  the  soil,  or  the 
vegetation  inhabited  by  the  insects.  Of  this  mode 
of  defence  the  beetle  family  offers  no  dearth  of  illus- 
tration. Among  Cicindela,  C.  campestris  frequents 
grassy  slopes  and  is  green  ;  C.  maritima  is  found 
only  on  sandy  shores  by  the  sea,  and  is  of  a  pale 
brownish  yellow.  Dr.  Wallace  discovered  many  of 
these  insects  in  the  Malay  Isles  invariably  in 
harmony  with  their  place  of  abode.  C.  gloriosa,  of  a 
velvety- green,  was  always  taken  on  wet  mossy  stones 
in  the  bed  of  some  mountain  stream,  the  brown 
C.  heros  chiefly  on  dead  leaves  in  the  forest  paths. 
The  wet  mud  of  salt  marshes  alone  furnished  a 
glossy-olive  species,  so  closely  corresponding  to  the 
colour  of  the  mud  that  it  was  only  distinguished,  when 
the  sun  shone,  by  its  shadow !  Where  the  beach  was 
coralline  and  nearly  white,  Wallace  saw  a  pale 
Cicindela  ;  where  it  became  volcanic  and  black,  a 
dark  species  of  the  same  genus  presented  itself.  A 


vi  DEFENCES  QF  INSECTS  209 

small  weevil  mercilessly  persecuted  by  ground-beetles 
abounds  in  pits  of  a  loamy  soil,  of  the  same  colour 
precisely  with  itself,  undoubtedly  facilitating  the 
escape  of  many  from  their  foe.  A  scarce  British 
weevil,  by  its  grey  colour  spotted  with  black,  is  an 
equally  good  counterpart  of  the  locality  where  it 
generally  seems  to  roam,  which  consists  of  white 
sand  mixed  with  black  earth. 

In  some  cases  a  species  confine  themselves  entirely 
to  one  species  of  tree,  whose  bark  they  simulate  in 
colour  and  rugosity.  They  are  excessively  abundant, 
and  surely  it  cannot  be  considered  exaggerated  to 
regard  the  protection  derived  from  the  resemblance 
as  a  factor,  and  no  small  one,  in  the  flourishing 
condition  of  the  race. 

Numbers  of  our  weevils  and  other  beetles  when 
alarmed  drop  off  the  leaves  on  which  they  are  sitting, 
at  the  same  time  rolling  themselves  into  little  lumps 
or  balls.  It  is  useless  to  look  for  them  on  the 
ground,  where  they  lie  motionless  amid  stones  and 
earth-pellets,  the  appearance  of  which  they  simulate 
exactly. 

The  fact  is  well  known  that  however  gay  the 
upper  surfaces  of  the  wings  of  butterflies  may  be,  the 
undersides  are  nearly  always  sober,  often  very  dull 
and  obscure,  and  in  some  instances  have  been  observed 
to  be  like  the  surfaces  whereon  the  insects  customarily 
rest.  This  arrangement  of  colour  is  eminently'pro- 
tective,  because  during  prolonged  repose  a  butterfly 
takes  care  to  hold  its  wings  raised  perpendicularly 
over  the  back,  effectually  to  conceal  its  lovely  but 
treacherous  possession.  Moths  usually  have  their 

P 


210 


ROMANCE  OF  THE  INSECT  WORLD      CHAP. 


chief  colour  on  the  hind  wings,  the 
fore  ones  are  dowdy  and  often  imita- 
tive in  tint,  and  generally  cover  the 
lower  pair  when  the  insects  are  not 
in  flight.  Probably  a  thorough  exami- 
nation of  the  habits  of  our  butterflies 
would  reveal  their  under  surfaces  to 
be  much  more  frequently  imitative 
than  at  present  we  believe  to  be  the 
case.  The  concealment  afforded  by 
this  means  is  effective,  judging  by 
the  total  disappearance  of  common 

FIG.     36. — The      cater-  _ .  -11  ,1  1171-1 

pillar  of  Early  Thom    butterflies   m   bad  weather.      While 

Moth     (Selenia    illu-  1111  •     , 

naria),  showing  sup-    some  take  shelter  by  creeping  into 

porting  thread  of  silk  ;  ,1-1 

from  Trans.  Entom.  nooks  and  corners  among  thick-set 
leaves,  others  cling  freely  exposed  to 

surfaces  that  blend  harmoniously  with  their  own  tints. 
To  pass  on  to  the  more  specialised 
forms  of  protective  resemblance,  not 
confined  to  colour,  but  which  extend 
to  outline  and  shape,  and  deal  with 
the  attitudes  of  the  insects.  As  com- 
bining all  these  several  features,  no 
better  instance  could  be  found  than 
that  offered  by  the  caterpillars  of 
the  Geometrae  moths,  "stick-cater- 
pillars," or  surveyors,  or  loopers,  as 
they  are  popularly  called.  For  hours 

FIG.  37.— Appearance  of    together  these  larvae  will  sit  motion- 

the  larva  of  Brimstone  & 

Moth  (Rumia  crat#-    jess    projecting   at   an    angle   more 

gata)     when     seated  >     Jr      J 

among  the  twigs  of  its          jess   acute  from    the   bushes   on 

commonest  food-plant; 

from  Trans.  Entom.    wri}cri    they    feed    looking    for    all 

OCt  * 


VI 


DEFENCES  OF  INSECTS 


211 


the  world  like  the  plant's  own  branches.  The 
caterpillar  is  long,  slender,  and  cylindrical,  it  holds 
itself  stiff  and  immovable,  so  as  to  hide  as  far 
as  may  be  the  separations  of  the  segments,  and  its 
free  end  where  it  terminates  in  the  head  one  imagines 
to  be  the  bud  at  the  end  of  a  twig.  Little  humps  or 
tubercles  likewise  frequently  exhibited  on  the  body 
pass  readily  for  additional 
buds  or  irregularities  of  the 
bark,  and  tend  greatly  to  in- 
crease the  resemblance.  The 
likeness  is  promoted  by  the 
peculiar  disposition  of  the  legs. 
While  the  majority  of  larvae 
have  five  pairs  of  claspers,  or 
legs  persistent  only  in  the 
caterpillar  state,  Geometrae 
possess  but  two  pairs  attached 
to  their  anal  extremity.  With 
them  the  caterpillar  firmly 
grasps  the  stem,  rendering 
them  very  inconspicuous,  and 
to  preclude  the  appearance 
of  any  limbs,  the  pairs  of  true 

legs  immediately  behind  the  head  in  many  cases  are 
applied  closely  to  the  body.  The  twig-like  attitude 
is  abandoned  solely  for  feeding,  which  as  a  rule  takes 
place  in  the  evening  or  at  night  (see  Fig.  35). 

On  the  face  of  it,  this  posture  seems  one  impossible  to 
be  borne.  No  creature  fashioned  horizontally  with  the 
surface  would  be  capable  of  erecting  itself  at  an  acute 
angle  with  its  support,  and  of  continuing  to  keep  the 

P  2 


FIG.  38.— The  hind  part  of  the 
larva  of  Brimstone  Moth 
\Rumia.  cratagata))  seen  from 
the  right,  showing  the  claspers 
and  the  fleshy  projections  which 
tend  to  fill  up  the  furrow  be- 
tween the  larva  and  the  stem  ; 
from  Trans.  Entoiii.  Soc. 


212  ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

position  for  any  lengthened  period.  Unaided,  the 
caterpillar  does  not  make  the  attempt.  Fatigue  is 
obviated  by  spinning  a  thread  of  silk,  which  is  fastened 
at  one  end  to  the  stem,  the  other  end  remains  attached 
to  the  head  of  the  insect  (see  Fig.  36).  That  there  is  con- 
siderable tension  upon  the  brace  may  be  seen  by  cutting 
it,  when  the  larva  falls  back  with  a  sudden  jerk.  In 
some  cases  the  caterpillar  is  enabled  to  endure  the 
strain  by  holding  a  leaf  or  twig  with  one  of  its  pairs  of 
articulated*  legs. 

Many  points  of  detail  concur  to  promote  this  de- 
ception of  Geometrae.  The  head  is  modified  from  its 
normal  shape  into  one  extremely  suggestive  of  the 
top  of  a  twig,  or  some  vegetable  growth,  or  at  least  to 
convey  no  hint  of  its  real  caterpillar  nature.  Com- 
monly it  is  notched,  a  plan  forming  a  very  natural 
end  to  the  apparent  twig.  In  the  caterpillar  of  the 
Small  Emerald  Moth  the  segment  behind  the  head  is 
humped  as  well,  while  the  latter  is  retracted,  so  that 
four  blunt  projections  are  produced,  carrying  out  yet 
more  admirably  the  resemblance  to  a  twig.  Similar 
unevennesses  are  obtained  by  the  head  and  first  body- 
rings  being  bent  backwards  (see  Fig.  36).  It  might 
be  supposed  that  the  claspers  by  which  the 
stem  is  held  would  excite  attention  and  betray 
the  insects.  They  however  partially  surround  the 
branch,  and  appear  to  grow  out  of  it  (see  Figs.  37 
and  38).  Lest  the  intervening  space  between  the 
front  and  hind  pairs  should  reveal  the  fraud,  the 
underside  of  the  larva  is  somewhat  flattened,  so  that 
it  lies  in  contact  with  a  small  portion  of  the  round 
stem,  On  either  hand  the  furrow  is  decreased,  in 


vi  DEFENCES  OF  INSECTS  213 

some  species  at  any  rate,  by  the  presence  of  fleshy  pro- 
tuberances (see  Fig.  38).     The  colour  of  the  larvae  is 


FIG. 39. — Leaf-Butterfly  in  flight  and  in  repose  ;  from  Wallace. 

usually  obscure,  in  general  agreement  with  that  of  the 
bark  of  a  tree  ;  sometimes  the  various  tints  of  a  stem 


2i»4          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

are  reproduced  with  marvellous  fidelity.  The 
Geometrae  are  a  widespread  and  numerous  tribe, 
divided  into  an  immense  number  of  species — there 
are  between  two  and  three  hundred  in  this  country 
alone,  a  result  that  has  been  brought  about,  doubtless, 
by  their  acquisition  of  a  form  and  attitude  so  well 
suited  for  purposes  of  concealment,  admitting  of  their 
success  in  life's  race,  to  the  detriment  of  larvae 
with  less  perfected  methods.  In  their  wanderings 
Geometrae  have  come  to  feed  upon  a  variety  of  food 
plants.  These  changes  have  in  some  cases  necessitated 
corresponding  modifications  of  attitude,  of  colour,  or 
of  form,  in  order  to  bring  the  larvae  into  harmony 
with  their  environments. 

Caterpillars  of  other  groups  secure  protection  by  the 
imitation  of  surrounding  vegetative  objects,  though 
perhaps  hardly  to  such  an  astonishing  degree.  Some 
resemble  the  bark  of  thick  branches,  and  repose  against 
the  bark,  closely  adhering  to  it.  The  furrow  that 
they  would  make  with  the  branch  is  obliterated  by 
hairs,  or  by  a  row  of  fleshy  projections,  at  least  in  all 
probability  this  is  the  use  of  these  structures.  The 
appearance  of  lichens*  is  also  commonly  simulated  by 
larvae  that  ordinarily  rest  on  lichen-covered  bark. 
"  Stick  caterpillars "  in  the  earlier  portion  of  their 
career  do  not  stand  upon  the  branches,  but  upon  the 
leaves  of  the  plant  on  which  they  feed,  where  the 
twig-like  attitude  would  be  inappropriate.  Some  are 
green  in  colour,  so  that  they  correspond  with  the 
leaves  ;  in  other  cases  the  caterpillars  are  brown,  as  at 
later  times,  and  the  attitude  is  then  often  modified  to 
avoid  danger.  Twisting  itself  into  spiral  or  zigzag 


vi  DEFENCES  OF  INSECTS  215 

shape,  the  insect  passes  muster  as  a  bit  of  dead  and 
curled  up  leaf,  or  as  the  excreta  of  birds  or  snails. 
Imitation  of  the  excrement  of  birds  is  however  rare 
and  exceptional. 

In  mature  Lepidoptera,  the  most  wonderful  and 
undoubted  case  of  the  higher  form  of  protective 
resemblance  is  that  of  the  Malayan  Leaf-butterfly, 
Kallima  paralekta,  and  its  Indian  ally  K.  inackis.  The 
method  of  concealment  has  been  described  by  Dr. 
Wallace,  who  was  the  first  to  observe  it,  in  his  Malay 
Archipelago,  and  elsewhere.  The  upper  surfaces  of 
the  wings  are  showy,  conspicuous,  and  large,  with  a 
broad  rich  orange  band  across  the  fore-wings  on  a 
deep  bluish  ground.  Opposed  to  this  brilliancy  the 
under  surfaces,  though  varying  greatly,  in  every  case 
are  of  sombre  tint,  of  some  shade  of  gray,  or  brown,  or 
ochre,  such  as  is  common  among  dead  or  withered 
leaves.  'Mid  leaves  of  the  kind  on  a  nearly  upright 
twig  the  butterfly  rests,  and  in  this  position  with  the 
wings  tightly  closed  over  the  back,  thus  exhibiting 
their  under  surfaces,  is  in  exact  agreement  with  its 
surroundings,  the  irregular  outline  of  the  folded  wings 
forming  a  direct  and  finished  representation  of  a 
moderate  sized  leaf,  shrivelled  or  withered  in  some 
stage  of  decay.  The  tip  of  the  fore-wing  is  produced 
into  a  point,  a  common  form  of  leaves  in  the  tropics  ; 
the  hind-wings  terminate  in  a  short  narrow  tail,  which 
touches  the  branch,  and  typifies  a  perfect  leaf-stalk. 
From  end  to  end  along  the  whole  length  of  the 
supposed  leaf  runs  a  distinct  dark  line,  the  seeming 
mid-rib ;  from  this  on  either  side  radiate  oblique  lines 
imitative  of  a  leaf's  lateral  venation.*  The  butterfly 


216          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

disposes  of  the  rest  of  its  body  so  as  to  bear  out  the 
deception.  In  place  of  keeping  its  head  and  antennae 
in  motion,  a  custom  with  butterflies,  Kallima  does  not 
expose  these  parts,  and  draws  them  back  out  of  sight 
between  the  bases  of  the  wings.  The  middle  pair  of 
legs  by  which  the  insect  clings  to  the  branch,  and 
keeps  the  "leaf"  in  due  position,  are  slender  and 
almost  invisible  among  the  twigs  and  fibres  that 
.surround  it  (see  Fig.  39). 

Dead  or  withered  leaves  are  often  attacked  in 
different  places  by  various  kinds  of  minute  fungi, 
and  are  pierced  with  holes  by  insect  larvae.  In 
conformity  with  their  patterns,  extraordinary  to 
say,  the  undersides  of  the  wings  of  the  butterflies 
exhibit  representations  of  blotches  and  mildew. 
In  many  cases  they  are  irregularly  covered  with 
patches  and  spots,  so  closely  resembling  fungi  found 
on  dead  leaves  that  it  is  almost  impossible  to  believe 
the  creatures  in  truth  are  not  suffering  from  incursions 
of  real  fungi.  Their  semblance  of  a  larva's  hole  is 
equally  accurate  and  telling.  The  scales  covering  the 
wings  are  absent  from  a  window-like  naked  spot  on 
each  fore -wing,  which  is  therefore  only  clothed  with 
the  thin  transparent  wing  membrane.  When  the 
butterfly  raises  its  wings  in  the  position  of  rest  these 
spots  come  together,  producing  the  effect  of  a  hole, 
since  the  two  membranes  are  almost  of  the  trans- 
parency of  glass. 

Colour,  form,  size,  and  habits  have  thus  each  their 
parts  to  play  in  this  marvellous  resemblance,  and  that 
it  affords  protection  is  shown  by  the  abundance  of  in- 
dividuals that  possess  it.  To  the  habits  of  the  butter- 


VI 


DEFENCES  OF  INSECTS 


217 


fly  is  assigned  not  the  least  important  role.  Of  what 
avail  would  be  the  disguise  were  the  insect  prone  to 
settle  upon  a  flower,  or  green  leaf,  or  other  inappro- 
priate surface,  or  to  open  its  wings  and  display  its 
attractive  colouration.  The  Malayan  species  seems  to 
be  as  wary  during  the  brief  pauses  between  the  flights 
as  during  lengthened  rest.  Dr.  Wallace  has  observed 
scores  of  K.paralekta  in  Sumatra,  where  they  frequent 


FIG.  40.— "A  Walking  Leaf"  Insect  ;  from  Belt. 

dry  woods  and  thickets,  and  they  were  never  seen  to 
settle  but  on  bushes  or  trees  with  dry  or  dead  leaves. 
They  settled,  and,  as  if  by  magic,  were  lost.  Search 
for  them  on  these  occasions  was  usually  in  vain,  for 
while  gazing  intently  at  the  very  spot  where  one  had 


2i8          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

disappeared  it  would  suddenly  dart  out,  and  again 
vanish  a  few  yards  farther  on.  But  the  butterfly  has 
been  detected  reposing,  and  its  close  assimilation  with 
the  surrounding  leaves  was  then  evident.  The 
flight  of  Kallima  is  swift,  a  circumstance  affording 
great  assistance  to  the  fraud.  In  a  recent  paper,  Mr. 
S.  B.  J.  Skertchly  calls  attention  to  the  fact  that  leaf- 
mimickers  of  several  genera — and  Kallima  among 
them — settle  in  a  totally  different  manner  from  that 
of  other  butterflies.  The  latter  when  about  to  alight 
gradually  slacken  speed,  but  the  leaf-butterflies  '  fly 
rapidly  along,  as  if  late  for  an  appointment,  suddenly 
pitch,  close  their  wings,  and  become  leaves.' 

Keen  observation  would  probably  bring  to  light 
many  cases  of  special  protective  resemblance  among 
our  British  and  European  moths.  Such  as  Agriopis 
aprilina,  Acronycta  psi,  and  many  others  which  re- 
main by  day  on  the  sides  of  trunks  of  trees  so  exactly 
resemble  the  gray  and  green  lichens  that  cover  the 
bark  as  to  be  distinguished  with  difficulty.  Bryophila 
and  many  Geometers  are  the  very  images  of  the  mortar 
walls  or  the  surfaces  of  stones  that  they  frequent. 
Numerous  gray  and  white  Geometers  which  rest  on  the 
upper  sides  of  leaves  forcibly  suggest  the  excreta  of 
birds.  The  well-known  Buff-tip  Moth  (Pygcem  buce- 
pJiala]  is  admirably  disguised  by  resembling  a  broken 
end  of  a  decayed  and  lichen  covered  branch,  the 
cylinder-like  effect  being  obtained  by  the  wings  being 
carried  round  the  body.  The  Lappet  Moth  is  also 
very  perfectly  concealed  by  resembling  an  arid  brown 
leaf,  both  in  shape  and  colour.  As  seen  in  flight,  the 
Yellow  Underwing  (Triph&na pronubd]  might  likewise 


vi          DEFENCES  OF  INSECTS         219 

be  mistaken  for  a  withering  leaf  tossed  along  by  the 
wind.  The  Herald  Moth  (Gonoptera  libatrix],  one  of 
the  most  beautiful  of  these  imitations,  represents  a 
red-brown  leaf  having  succumbed  to  a  certain  amount 
of  white  fungoid  growth.  Lest  its  bright  eyes*  should 
expose  the  deception,  a  tuft  of  hair  falls  over  them  and 
conceals  them  during  rest.  The  delicate  veil  is  easily 
raised  as  the  insect  takes  to  flight. 

It  has  been  remarked  that  a  striking  harmony 
exists  between  the  colours  of  the  British  autumn  and 
winter  moths  and  those  that  prevail  in  the  respective 
seasons.  In  autumn  vegetation  as  a  whole  dons  a 
sober  brown  and  yellow  livery,  and  out  of  fifty-two 
species  then  on  the  wing,  forty-two  are  of  correspond- 


FIG.  41. — A  "  Walking-Stick,"  or  Moss  Insect ;  from  Belt. 

ing  shades.  Gray  and  silver  are  the  characteristic 
tones  of  nature's  winter  garb,  and  accordingly  these 
tints  predominate  in  the  winter  moths. 

The  Lcpidoptera  apart,  the  whole  order  of  Orthop- 
tcra  (grasshoppers,  locusts,  crickets,  &c.)  will  be  found 
to  be  signally  happy  in  respect  of  the  possession  of  this 
protection,  every  grade  in  resemblance  being  repre- 


220          ROMANCE  OF  THE  INSECT  WORLD      CHAP, 
sented,  from  a  general  harmony  with  the  vegetation 


FIG.  42. — Imitation  of  a  Flower  by  a  Mantis  (Hymenopus  bicoinis)  in  active  pupa 
stage  ;  after  Wallace. 

or  soil  commonly  surrounding  them  up  to  the  most 


vi  DEFENCES  OF  INSECTS  221 

striking   examples   of    special    imitation    of  definite 
objects.     Many  of  the  tropical  Locustidae  and  Phas- 
midae,  in  the  colour,  texture,  and  veining   of  their 
elytra,  are  like  green  leaves  ;  others  represent  leaves 
in  various  states  of  decay.     In  none  the  dissimulation 
is  carried  to  greater  extent  than   in  the  wonderful 
genus    Phyllium,   "  the  walking-leaf"    (see    Fig.  40). 
Not  only  have   the  wings  assumed    the  appearance 
of  leaves,  the  thorax  and  legs  have  been  equally  adap- 
tive, and  have  become  flat,  expanded  and  leaf-like,  to 
the  elimination  of  their  ordinary  forms.     When  the 
insect  is  resting  among  its  food-plant  often  the  closest 
scrutiny  fails  to  distinguish  the  difference  between  the 
animal  and  the  vegetable.     Many  of  the  species  of 
Phasmidae — the  family  to  which  this  insect  belongs, 
the  "  spectres "   or    "  praying   insects "    as   they    are 
popularly    called — are    known    as    "  walking-sticks," 
from  their  singular  resemblance  to  twigs  and  branches. 
Their  colouring,  form,  rugosity,  and  arrangement  of 
the  head  and  legs  are  all  in  accurate  accord  with  the 
appearance  of  dead  sticks  ;  in  a  word,  when  "  walking- 
sticks  "  are  seen  stationary  it  seems  scarcely  credible 
that  an   imposture  is   being  played.     In  Brazil,  and 
elsewhere,   some  are  no   less  than   eight  inches  and. 
even  a  foot  long  and  of  the  thickness  of  one's  finger. 
They  hang   about    shrubs   in  forests,   and  have  the 
extraordinary  habit  of  holding  out  their  limbs  unsym- 
metrically,  the  better  to  typify  a  branch  with  lateral 
spray  (see  Fig.  41). 

In  a  case  recorded  by  Dr.  Wallace  the  trickery 
does  not  end  here.  A  "walking-stick"  (Ceraxylus 
laceratus)  obtained  in  Borneo  exactly  resembles  a 


222          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

stick  grown  over  by  a  creeping  moss  or  junger- 
mannia,*  an  appearance  due  to  certain  foliaceous 
excrescences  or  irregularities,  of  a  clear  olive-green 
colour.  So  absolutely  identical  were  the  counterfeit 
and  the  reality,  the  native  Dyak  who  brought  in 
the  insect  maintained  it  was  grown  over  with  moss, 
although  alive,  and  it  was  only  after  minute  ex- 
amination that  Dr.  Wallace  could  convince  him- 
self that  the  fact  was  not  so.  The  change  of 
character  is  pronounced.  In  Darwin's  opinion  there 
is  nothing  improbable  in  this  insect  having  varied  in 
the  irregularities  on  its  surface,  and  in  these  having 
become  green. 

Importance  is  attached  to  the  details  of  form  and 
colour  in  the  Beetle  family.  The  small  Buprestidse, 
for  example,  which  generally  rest  on  the  mid-ribs  of 
leaves,  closely  resemble  the  excrement  of  birds. 
Chlamys  pihila  is  undistinguishable  from  the  dung  of 
caterpillars.  The  genus  Chlamys  furnishes  another 
illustration  of  this  method  of  concealment  and  pro- 
tection in  a  brilliant  and  beautiful  beetle,  said  to 
suggest  some  kinds  of  fruit  by  the  inequalities  of  its 
red-coloured  surface.  Some  of  the  Cassidae,  from  their 
shape  and  colour,  sparkle  like  dew-drops  upon  leaves. 
From  the  Heteroptera  we  get  a  representation  of  a 
withered  and  crumpled  leaf,  with  the  edges  turned  up 
and  eaten  away,  as  if  by  caterpillars.  Some  bugs 
simulate  leaves  in  skeleton, when  the  parenchymatous* 
portion  has  disappeared  and  the  network  alone  is 
left.  Spiders  are  often  protectively  coloured,  and 
imitate  the  lichen  on  tree-trunks  (as  Philodromus). 
They  are  eagerly  sought  by  insectivorous*  animals,  so 


vi          DEFENCES  OF  INSECTS         223 

that  the  resemblance  is  doubtless  to  their  immense 
advantage.  In  many  cases,  however,  their  adaptation 
is  chiefly  aggressive,  enabling  the  spiders  to  capture 
their  prey. 

Turning  to  Aggressive  Resemblances,  certain  car- 
nivorous insects,  as  the  Mantidce,  are  well  concealed 
by  harmonising  with  their  surroundings.  This, 
though  to  a  large  extent  protective,  also  assists  them 
to  creep  upon,  or  to  lie  in  wait  for,  their  prey. 
Aggressive  Resemblance  becomes  of  more  than 
ordinary  interest  when  it  not  only  screens  an  insect 
from  its  prey,  when  it  simulates  some  object  pleasing 
or  attractive  to  the  latter,  and  so  induces  its  approach 
— it  acts  as  a  lure,  and  entices  the  unsuspecting  victim 
into  the  spot  for  convenient  capture,  into  the  very 
jaws  of  death.  Species  of  mantis,  both  from  India 
and  Africa,  are  endowed  with  this  dangerous 
fascination.  They  have  all  the  appearance  of  fine 
flowers,  things  of  special  value  to  insects  of  vegetarian 
tastes.  They  draw  near,  and  of  course  are  greedily 
made  away  with  by  the  seeming  blossoms. 

Hymenopus  bicornis,  a  mantis  of  great  rarity,  in- 
habiting India  and  Java,  in  active  pupa  is  an  inimitable 
representation  of  a  flower.  Colour,  form,  and  attitude 
all  conspire  to  produce  the  remarkable  deception  (see 
Fig.  42).  These  mantises  may  be  white  or  pink. 
The  thighs  of  the  four  posterior  legs  are  expanded 
into  broad  pear-shaped  plates,  constituting  the  appa- 
rent petals,  and  when  the  species  is  seated  they  are 
spread  out  two  on  each  side,  while  the  fore-legs  are 
tucked  out  of  sight  under  the  thorax.  There  need 
be  not  the  slightest  hesitation  in  stating  that 


224          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

even  butterflies  are  attracted,  as  insects  to  flowers, 
and  the  deceivers  feed  on  the  dupes  allured.  An 
equally  interesting  instance  of  this  striking  simu- 
lation is  exhibited  by  another  Indian  mantis, 
Gongylus  gongylodes  (Linn.).  It  is,  however,  only 
the  under  surface  of  the  animal  that  displays  the 
resemblance.  The  leaf-like  prothoracic  *  expansion, 
instead  of  being  green,  is  of  a  clear  pale  lavender- 
violet  colour,  inclining  to  mauve,  and  acquiring  a 
reddish  tinge  towards  the  margins,  and  with  a 
black-brown  blotch  in  the  centre,  representing 'the 
opening  of  a  tube  in  the  middle  of  a  flower's  corolla. 
The  insect  is  addicted  to  hanging  head  downwards 
amongst  a  mass  of  green  foliage,  and  remains  motion- 
less, or  occasionally  sways  about  like  a  flower  touched 
by  a  gentle  breeze.  With  its  fore-limbs  banded  violet 
and  black,  and  drawn  up  in  the  centre  of  the  corolla, 
it  looks  exactly  like  a  papilionaceous  *  flower.  The 
disguised  limbs  act  as  a  decoy  to  insects,  which  fly 
directly  into  the  sabre-like  raptorial  *  arms  of  the 
simulator.1 

The  resemblances  of  spiders  to  flowers  are 
probably  chiefly  cases  of  the  same  offensive  dis- 
guise, as  opposed  to  purely  defensive  imitations. 
The  bunches  of  blossom  of  the  way-faring  tree, 
Viburnum*  have  been  observed  to  be  occupied  by 
spiders  of  a  pale  creamy  white,  the  exact  tint  of  the 
flowers,  and  their  abdomen  closely  resembled  the 
unopened  buds — of  which  there  were  many  in  each 
cyme — not  only  in  colour,  but  in  size  and  shape. 
These  spiders  are  by  nature  hunters  and  not  web- 
1  Proc,  Entom.  Soc.,  1877,  xlix, 


vi  DEFENCES  OF  INSECTS  225 

spinners,  and  the  number  and  variety  of  insects  that 
visited  the  blossoms  were  great.  Somewhat  later 
in  the  year  similar,  if  not  identical,  kinds  were  seen 
on  the  wild  guelder-rose,  and  on  Orchis  maculata. 
Many  bushes  of  the  mealy  Viburnum  were  growing 
close  by,  but  their  blossoms  were  over.  The  spider 
on  the  guelder-rose  had  reddish-brown  spots  on  the 
side  of  the  abdomen,  but  not  sufficiently  distinct  to 
interfere  with  the  perfection  of  the  disguise.  But 
in  the  case  of  the  one  on  Orchis  maculata  the  spots 
on  the  sides  of  its  abdomen  were  large,  of  a  dark 
red-brown  colour,  and  very  sharply  defined  ;  and 
when  he  stood  in  his  usual  position,  with  his  head 
downwards,  they  very  clearly  resembled  in  size, 
shape,  relative  position,  and — at  a  yard's  distance 
— even  in  colour  the  dark  purple  pollinia  *  of  the 
flowers.  Though  many  of  these  spiders  were  present 
on  Orchis  maculata,  not  a  single  one  could  be  dis- 
covered on  the  dwarf  orchis  (O.  ustulata),  which  is 
much  like  maculata,  but  its  pollinia  are  not  dark. 
Mr.  Nottidge  suggests  that  as  the  season  advances 
these  spiders  change  colour,  and  each  successive 
change  specially  adapts  them  for  concealment  on  the 
blossom  of  some  special  plant.1  Mr.  Jenner  Weir2 
has  also  seen  these  spiders  (Thomisus  citreus)  station 
themselves  in  the  centre  of  a  composite  *  flower,  with 
their  legs  expanded  like  its  exterior  rays,  and  some- 
times in  the  flowers  of  orchids,  with  their  legs  ex- 
panded horizontally.  Apparently  they  are  capable  of 
destroying  even  the  honey-bee,  which  he  has  found 
dead  in  their  clutches. 

1  Proc,  Entom.  Soc.,  1878,  xl.,  xli.  2  Loc.  cit. 

Q 


226          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

Beautiful  examples  of  Alluring  Colouring  occur  in 
the  resemblance  of  Mantidae  to  the  excreta  of  birds. 
Flies  are  often  attracted  by  such  droppings,  and  the 
Mantidae  take  advantage  of  this  fact  to  secure  their 
prey.  A  similar  instance  was  discovered  by  Mr. 
Forbes  in  Java,  in  a  spider  (Ornithoscatoides 
decipiens),  whose  imitation  of  a  bird's  dropping 
from  a  height  on  a  leaf  is  carried  out  with  minute 
detail — colouring,  form,  and  habits  contributing  to 
the  success  of  the  resemblance  (see  Fig.  43).  This 
is  one  of  the  most  remarkable  instances  of  faithful 
assimilation  of  an  animal  to  a  vegetative  or  inanimate 
object,  and  affords  a  wonderful  example  of  what  is 
in  the  power  of  natural  selection  to  accomplish.  The 
principle  of  natural  selection  alone  is  sufficient  to 
explain  the  case,  for  the  acquisition  of  every  new 
grade  in  the  likeness  would  at  once  give  the  owner 
an  advantage  in  the  continual  struggle  for  food. 

In  the  foregoing  cases  of  protective  resemblance 
the  imitated  objects  are  constant  in  their  nature,  and 
the  disguising  characters  of  the  imitating  species 
remain  constant  throughout  the  lifetime  of  each 
individual.  As  regards  leaf-butterflies  and  others 
which  resemble  withered  leaves,  the  constancy  of  the 
individual  is  no  less  perfect,  but  the  imitated  objects 
vary  slightly  in  hues,  calling  forth  a  corresponding 
variability  of  colour  among  the  copying  species. 
There  are  a  few  examples  where  each  insect  under- 
goes a  rapid  change  of  colour  once  during  its  lifetime. 
It  acquires  a  new  habit,  entailing  change  of  environ- 
ment, and  with  the  fresh  surroundings  relationship 
must  be  set  up.  Obviously  this  change  of  habit  in 


vi  DEFENCES  OF  INSECTS  227 

the  species  is  equivalent  to  a  change  of  character  in 
the  imitated  object.  Among  insects  in  this  class  may 
be  mentioned  the  larva  of  Sphinx  ligustri.  When 
full-fed  previous  to  pupation,  it  deserts  its  food- 
plant  and  descends  to  the  ground  to  find  a  suitable 
burying-place,  where  its  bright  green  coat  would  be 
conspicuous  and  rife  with  danger.  Accordingly  the 
caterpillars  lose  their  original  colour,  and  become 
brown,  bringing  them  into  consonance  with  their  new 
surroundings.  Professor  Meldola  was  the  first  to 
perceive  the  true  meaning  of  this  change.  An  in- 
stance is  afforded  by  Geometrse  of  exactly  the  op- 
posite alteration  at  a  corresponding  period.  In  its 
young  days  the  larva  (Ennomos  angularia)  is  a  brown 
"  stick-caterpillar,"  and  receives  special  protection 
from  its  resemblance  to  twigs.  Eventually  it  forms 
a  cocoon  of  green  leaves  loosely  put  together,  so  that 
its  body  is  plainly  visible  through  the  leafy  screen 
But  at  the  same  time  its  brown  colour  disappears,  and 
its  surface  becomes  green,  due  to  its  green  blood, 
which  is  visible  through  the  transparent  skin. 

The  tendency  in  caterpillars  is  to  become  dull  in 
colour  on  the  approach  of  pupation,  and  these  inci- 
dental changes,  in  all  probability,  have  constituted 
the  accidental  resemblance  to  the  soil,  the  initial  start 
as  it  were,  from  which  the  definite  alteration  has  been 
developed  by  natural  selection.*  That  the  change 
must  sometimes  prove  disastrous  to  the  individual  is 
unquestionable.  If  at  this  crisis  of  life  a  caterpillar 
of  the  Privet  Hawk  Moth  were  to  descend  upon  turf, 
or  ground  covered  with  other  green  vegetation,  it 
would  still  turn  brown;  although  its  green  dress  would 

Q  2 


228          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

conceal  it  more   effectively.      But   assuredly  on  the 
whole    the   change    must    be    advantageous    to   the 


FIG.    43. — A  <Bird's  Excreta  mimicking  Spider ;  from  Forbes. 

species,  else  variations  conducing  to  it  would  not  have 
been  preserved,  but  would  have  been  neglected,  and 
finally  lost.  In  caterpillars  closely  allied  to  Sphinx 
ligustri,  which  feed  near  damp  green  soil,  the 
assumptionjof  brown  is  far  less  marked. 

These  alterations  in  colour  naturally  suggest 
other  differences  of  appearance  known  as  di-* 
or  polymorphism.  The  larvae  of  certain  insects 
regularly  appear  under  two  conspicuously  distinct 
forms,  chiefly  a  green  and  a  brown.  The  cir- 


VI 


DEFENCES  OF  INSECTS 


229 


cumstance  is  altogether  apart  from  sex,  and  seems 
to  exert  no  influence  upon  the  future  perfect 
insects.  Dimorphism  is  also  present  in  perfect 
insects,  in  the  Lepidoptera  especially  in  the  females. 
It  occurs  likewise  among  male  spiders.  As  regards 
ants  and  others  of  the  social  Hymenoptera,  the 


FIG.  44. — The  pupa  of  a  South 
African  Swallow-tailed  Butterfly 
(JPapilio  nireus)  attached  to  orange 
tree,  and  corresponding  in  colour 
to  its  deep  green  leaves ;  from 
Trans.  Entom.  Soc. 


FTG.  45. — The  pupa  of 
Papilio  nireus  at- 
tached to  wood -work, 
the  colour  of  which  it 
imitates  ;  from  Trans. 
Entom.  Soc. 


individual  differences  of  the  females  are  most  pro- 
nounced. Here,  however,  the  meaning  is  obvious 
since  each  form  is  set  apart  for  different  labour,  an 
arrangement  advantageous  to  the  society,  and  conse- 
quently to  the  species.  The  benefits  that  accrue  from 
larval  dimorphism  are  difficult  to  determine,  but  we 


230          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

may  depend  upon  it  that  advantages  to  the  species 
thereby  do  arise,  else  one  of  the  forms  would  be 
eliminated.  Probably  a  dimorphic*  species  is  better 
protected  than  one  which  is  non-dimorphic.  The 
larvae  of  the  former  have  a  wider  range  of  resem- 
blances to  the  tints  and  objects  of  nature,  and  there- 
fore more  chances  of  concealment  and  escape  from 
enemies.  Dimorphism  would  also  seem  to  bestow 
greater  adaptability  on  the  part  of  a  species  to  new 
scenes.  In  its  wanderings  one  of  its  forms  may  be 
well  protected  in  the  new  country  ;  in  other  countries 
the  other  form  may  be  more  concealed.  The  form 
best  in  harmony  with  the  new  situation  would  tend  to 
develop,  to  the  subduing  and  exclusion  of  the  other 
— a  command  of  resource  in  which  a  non-dimorphic 
species  would  be  far  inferior.  Natural  selection 
would  appear  to  be  the  power  at  work,  effecting 
the  disappearance  of  the  less  protected  variety. 

Among  perfect  insects  dimorphism  seems  to  in- 
dicate the  development  of  a  younger  from  an  older 
form.  One  form  is  usually  much  rarer  than  the 
other,  and  probably  the  older  of  the  two.  The  later 
development  may  be  ascribed  in  part  to  its  increased 
power  of  protection  of  the  species.  Although  in  most 
cases  the  two  or  three  forms  are  now  distinct,  it  is 
probable  that  they  were  formerly  connected  by 
intermediate  gradations.  Thus  Dr.  Wallace  describes 
a  butterfly  in  the  Malay  Archipelago  which  presents 
a  great  number  of  connected  varieties,  and  the  extreme 
links  of  the  chain  closely  resemble  the  two  forms  of 
an  allied  dimorphic  species  inhabiting  the  same 
country.  Darwin  also  points  out  that  though  with 


VT  DEFENCES  OF  INSECTS  231 

ants  the  several  worker-castes  are  generally  quite 
distinct,  in  some  cases  the  castes  are  connected 
together  by  finely  graduated  varieties.  Probably  the 
variations  simply  originate  in  the  many  slight  differ- 
ences which  appear  in  the  offspring  from  the  same 
parents.  No  one  will  suppose  that  all  the  individuals 
of  the  same  species  are  cast  in  the  same  actual  mould. 
These  individual  differences  are  often  inherited,  and 
thus  afford  materials  for  natural  selection  to  act 
on  and  accumulate.  It  doubtless  appears  a  very  re- 
markable fact  that  a  female  butterfly  (for  instance) 
should  be  able  to  produce  at  the  same  time  three 
distinct  female  forms  and  a  male.  But  these  cases 
"  are  only  exaggerations  of  the  common  fact  that  the 
female  produces  offspring  of  two  sexes  which  some- 
times differ  from  each  other  in  a  wonderful  manner."1 
I  must  pass  over  other  phases  of  di-  and  trimor- 
phism,*  and  polymorphism,  a  mere  extension  probably 
of  the  same  principle.  Enough  has  been  said  to  show 
that  this  subject  is  a  very  wide  one,  and  in  many 
cases  extremely  perplexing  and  very  obscure. 

A  series  of  phenomena  remain  to  be  considered 
which  cannot  be  better  described  than  as  by  far  the 
highest  and  most  important  class  of  di-  or  polymor- 
phism. As  in  dimorphism  the  species  have  two  or 
more  sets  of  appearances,  but  these  seem,  as  it  were, 
under  the  control  of  each  insect,  which  is  susceptible 
to  the  influence  of  the  surroundings,  and  can  at 
pleasure  assume  the  appropriate  form,  adjusted  to 
correspond  with  its  own  peculiar  environment.  In 
dimorphism  proper  it  is  the  species  that  tends  to 
1  Darwin.  Origin  of  Species. 


232          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

alter  its  appearance  in  order  to  adapt  itself  to 
surroundings,  due  to  natural  selection,  which  seizes 
upon  and  renders  definite  variations  which  are  of 
service  to  the  species.  In  Variable  Protective  Re- 
semblance, about  to  be  described,  each  particular 
individual  is  capable  of  adapting  itself,  of  altering  its 
form,  to  bring  it  into  consonance,  and  therefore 
protection,  with  the  various  conditions  that  it  is  likely 
to  meet  with  in  Nature.  Of  the  two  kinds  of 
dimorphism,  clearly  that  where  individual  suscepti- 
bility is  present  is  of  far  higher  protective  value. 

It  is  now  a  quarter  of  a  century  ago  since  Mr.  T. 
W.  Wood,  in  a  paper  read  before  the  Entomological 
Society  of  London,  stated  as  the  result  of  observations 
that  the  pupae  of  certain  Lepidoptera  corresponded  in 
colour  to  their  surroundings.  The  "  Garden  Whites  " 
he  had  found  to  be  dark  on  tarred  fences  and  in  sub- 
dued light,  while  these  pupae  were  light-coloured  when 
attached  to  light  surfaces.  In  the  same  way  the 
chrysalis  of  the  Large  Tortoiseshell  Butterfly  ( Vanessa 
bolyckloros)  was  coloured  like  a  withered  leaf  when 
suspended  among  foliage.  It  was  then  light  reddish- 
brown  with  metallic  silvery  spots,  while  a  specimen 
from  a  wall  was  mottled  gray  and  the  metallic  spots 
were  not  produced.  Between  1867,  the  date  of  these 
announcements,  and  the  present  day,  the  experiments 
of  various  observers  have  confirmed  the  truth  of  the 
general  principle  involved  in  Mr.  Wood's  researches. 
By  exposure  of  pupae  of  Lepidoptera  to  different 
surfaces,  it  has  been  proved  beyond  doubt  that  many 
possess  the  power  of  adjusting  their  colours  to  the 
normal  surfaces  to  which  they  are  fixed  (see  Figs.  44 


vi  DEFENCES  OF  INSECTS  233 

and  45).     This  extraordinary  capability  is  only  present 
in  exposed  chrysalides.*     Most  of  the  chrysalides  of 
butterflies  are  freely  exposed  ;  the  majority  of  moths 
pass  their  pupal  period  in  burrows  in  the  earth,  or 
enveloped  in  thick  cocoons,  and  among  these  sensi- 
tiveness to  surroundings  is  probably  entirely  absent. 
Up  to  1 886  the  fact  of  the  power  of  adjustment 
was  really  all  that  was  known  concerning  this  strange 
phenomenon,  and  the  manner  in  which  the  colours  of 
these  pupae  are  determined  was  a  mere  matter  of  specu- 
lative theory.     In  that  year  Mr.  Poulton  commenced 
his    elaborate    series    of  investigations,   which    have 
thrown  a  flood  of  light  on  this  important  subject.  It  was 
then  accepted  by  Mr.  Wood,  and  by  most  naturalists 
interested  in  the  question,  that  the  skin  of  the  pupa 
was  photographically  sensitive   for  a  few  hours  only 
after  the  caterpillar's  skin  had  been  shed.    Comparison 
was  made  with  the  sensitive  photographic  plate,  which 
darkens    under     the    influence    of    light.     Professor 
Meldola,  however,  subsequently  showed  this   photo- 
graphic sensitiveness  of  chrysalides  to  be  a  mistake, 
for  '  the   action   of  light  upon  the  sensitive  skin  of  a 
pupa  has  no  analogy  with  its  action  on  any  known 
photographic  chemical.     No  known  substance  retains 
permanently  the    colour  reflected   on   it  by  adjacent 
objects.'      This    groundless,    though    very  plausible, 
theory  was  completely  overthrown   by   Mr.  Poulton's 
simple  experiment    showing   the    animal's    period  of 
susceptibility  to  surroundings  to  be  in  fact  previous 
to  the  development  of  the  pupal  form.     From  a  small 
number    of   freshly-found    pupae     he    removed    one, 
immediately  after  the  larva  skin  was  shed,  to  a  sub- 


234          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

stance  of  another  colour,  known  to  produce  an  opposite 
effect  upon  the  pupa,  leaving  the  rest  of  the  company 
on  the  accustomed  site.  The  pupa  taken,  like  the 
pupae  left,  resembled  the  larval  surroundings,  and  not 
the  subsequently  chosen  surface.  Clearly  the 
surroundings  had  exercised  their  influence  ere  the 
pupa  was  removed. 

So  much  certain,  Mr.  Poulton1  had  now  to  ascertain 
the  exact  period  of  susceptibility  to  surroundings  of 
these  organisms.*  He  first  aimed  at  making  careful 
note  of  everything  that  happens  to  a  caterpillar 
between  the  cessation  of  feeding  and  the  change  to 
pupa,  for  he  felt  sure  that  the  time  of  susceptibility 
lay  somewhere  within  these  limits.  When  the  cater- 
pillars with  which  the  experiments  were  conducted  are 
full-fed,  he  tells  us,  they  descend  from  the  food-plant 
to  the  ground,  and  wander  about  in  search  of  a 
surface  on  which  to  pass  the  pupal  life.  This  Mr. 
Poulton  denominates  stage  I.  Having  selected  the 
spot  the  insect  rests  motionless  upon  it — stage  II. 
Lastly  the  larva  suspends  itself  head  downwards — 
stage  III.  At  the  end  of  this  time  the  skin 
splits,  exposing  the  chrysalis  which  eventually 
generally  gets  rid  of  the  now  useless  larval  skin. 
Stage  I.  seemed  to  Mr.  Poulton  to  be  out  of  count  as 
the  period  in  question,  since  even  if  the  caterpillars 
were  then  susceptible,  "  no  effective  results  could  be 
obtained  ;  for  they  are  then  wandering  over  surfaces  of 
various  colours,  of  which  few  can  be  the  same  as  that 
which  will  form  the  environment  of  the  chrysalis."  Mr. 

1  I  am  indebted  to  Mr.  Poulton's  Colours  of  Animals  for  this 
account  of  his  researches. 


vi  DEFENCES  OF  INSECTS  235 

Poulton  exposed  larvae  to  one  colour  during  stages  I. 
and  II.,  and  transferred  them  to  another  colour  for 
stage  III.  ;  other  larvae  were  exposed  to  each  of 
the  colours  for  all  three  stages  ;  and  the  effects  were 
compared.  Stages  II.  and  III.  both  showed  them- 
selves sensitive,  but  stage  II.  is  more  sensitive  than 
the  other.  For  the  larvae  which  Mr.  Poulton  exposed  to 
gilt  surroundings  during  stage  II.  and  to  black  after- 
wards, "were  lighter  than  those  which  had  been  exposed 
to  black  during  stage  II.  and  to  gilt  afterwards." 
That  both  stages  are  sensitive  is  proved  by  the  fact 
that  "  the  black  and  gilt  surroundings  produced  still 
greater  effects  when  they  operated  for  the  whole 
period  before  pupation." 

Thus  the  old  theory  of  photographically  sensitive 
chrysalides  falls  to  the  ground.  As  Mr.  Poulton 
points  out,  the  adjustment  of  the  pupal  colours 
to  their  surroundings  is  due  to  larval  susceptibility, 
and  the  larva  itself  has  ceased  to  be  highly  sensitive 
many  hours  before  pupation.  That  stage  II.  is  the 
great  period  of  susceptibility,  probably  explains  the 
true  meaning  of  the  motionless  rest  of  the  larva  on 
the  surface  upon  which  it  will  pupate  ;  while  stage 
III.  has  other  meanings  connected  with  the  rapid 
pupal  changes  that  are  taking  place. 

The  next  question  was  to  determine  the  organ 
or  part  of  the  larva  which  is  affected  by  surrounding 
colours.  Mr.  Poulton  thought  that  the  eyes  (ocelli*}, 
or  the  bristles  which  cover  the  caterpillars,  might 
be  sensitive.  Neither  of  these  proved  to  have 
anything  to  do  with  the  influence.  In  one  set  of 
experiments,  out  of  a  number  of  larvae  placed  in  the 


236 


ROMANCE  OF  THE  INSECT  WORLD      CHAP. 


same  surroundings,  half  the  company  were  deprived 
of  their  bristles,  yet  the  pupae  from  the  normal 
and  from  the  mutilated  insects  were  identical.  Many 
other  experiments  in  which  half  of  the  larvae  were 
precluded  from  using  their  eyes,  showed  conclusively 

that  the  sensitive  organs 
had  some  other  position  in 
the  animal,  for  the  result- 
ing pupae  from  both  sets 
of  larvae  were  alike.  Mr. 
Poulton  was  thus  driven 
to  believe  that  the  general 
surface  of  the  skin  of  the 
caterpillar  is  susceptible 
to  colour.  To  test  this 
conclusion,  he  subjected 
the  body  of  the  same 
larva  to  two  conflicting 
colours,  producing  the 
most  opposite  effects 
upon  the  pupa.  A  care- 
ful comparison  of  all  the 
pupae  obtained  in  these 
experiments,  with  pupae 
obtained  from  larvae  fixed 

FIG.  46.-The  larva  of  Peppered   Moth     to  OllC  Colour  Ollly,  showed 
(Ainphidasis    betnlaria)   reared    amid       ,  .  ,    .  , 

green  twigs  and  leaves.  that  the     resulting   COlOUl'S 

tended  to  correspond  with 

the  surface  to  which  the  larger  area  of  skin  had  been 
exposed.  This  occurred  whether  the  head  formed 
part  of  that  area  or  not,  so  that  the  part  of  the 
body  containing  the  head  is  not  more  sensitive  than 


DEFENCES  OF  INSECTS 


237 


the  other  part,  confirming  Mr.  Poulton's  experiments 

to  the  effect  that  the  eyes  have  nothing  to  do  with 

the  influence.     The  influence  of  two  colours  did  not 

produce  parti-coloured  pupae,  as  some  observers   had 

suggested   might  be   the   case.      Had   parti-coloured 

pupae  been  obtained,  it  would  seem  probable  that  the 

light  acts   directly 

upon      the      skin. 

Since    they     were 

not     obtained,     it 

would  appear  that 

the     light     affects 

the  termination  of 

nerves  in  the  skin, 

"  and      that       the 

pupal    colours    are 

produced    through 

the  medium  of  the 

nervous  system." 

It  should  be  es- 
pecially noted  that 
certain  dimorphic 
pupae  show  not 
the  slightest  trace 
of  susceptibility  to 
the  surroundings.  The  chrysalis  of  the  Swallow- 
tailed  Butterfly  (Papilio  macJiaon),  for  instance,  appears 
in  two  forms,  being  sometimes  dark  and  sometimes 
green,  but  these  chrysalides  have  no  power  of 
adjustment  to  dark  and  green  surfaces  respectively. 
Fritz  Muller,  experimenting  upon  a  South  American 
Swallow-tail  {Papilio  poly  damns)  which,  like  our  own 


FIG.   47. — The  larva  of  Peppered  Moth  reared  amid 
dark-brown  twigs  as  well  as  leaves. 


238          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

has  dimorphic  pupae,  found  that  the  latter  are  equally 
non-susceptible  to  the  influence  of  adjacent  colours. 
The  caterpillars  of  some  of  the  Mocha  Moths 
(Ephyrida)  are  also  of  two  varieties,  and  the  pupae 
developing  therefrom  appear  in  two  colours,  answering 
to  those  of  the  larvae  from  which  they  sprang.  These 
pupae,  which  differ  from  the  pupae  of  many  moths  in 
being  freely  exposed,  are  likewise  insensitive  to  the 
tints  of  their  environment. 

Proceeding  now  to  Variable  Protective  Resemblance 
in  larvae,  the  larva  of  Ciiciillia  tanaceti  is  white  when 
it  is  feeding  on  the  leaves  of  the  mugwort  or  tansy, 
but  changes  to  yellow  when  it  is  confined  to  the 
flowers  of  the  latter.  Long  ago  Fabricius  observed 
that  the  larva  of  Bryophila  alg<z  varied  in  colour 
according  to  the  nature  of  its  food -plant,  being  yellow 
when  found  on  Lichen  juniperinus,  and  gray  when  on 
Lichen  saxatilis.  The  larva  of  Cleora  lichenaria  is 
wonderfully  adapted  to  the  lichen  on  which  it  feeds, 
and  differs  in  shade  of  colour  as  it  occurs  on  a  light- 
er dark-coloured  plant.  Another  example  of  similar 
variation  is  afforded  by  the  caterpillar  of  the  Eyed 
Hawk  Moth  (Smerinthus  ocellatus],  which  is  whitish 
gray  when  feeding  upon  certain  kinds  of  willow,  and 
of  a  bright  yellow  green  when  on  other  species  of 
willow.  The  fact  that  the  colour  of  the  caterpillars 
of  certain  species  may  differ  according  to  the  colour 
of  the  plant  on  which  they  occur,  is  especially  notice- 
able in  caterpillars  living  upon  the  petals  of  flowers, 
or  other  parts  of  brilliant  hue.  This  variability  has 
long  been  known,  and  it  was  most  natural  to  suppose 
it  due  to  the  direct  action  of  the  chlorophyll  or 


vi  DEFENCES  OF  INSECTS  239 

colouring  matter  of  the  different,  kinds  of  leaves 
on  the  tissues  of  the  insects,  the  more  so  from  the 
total  absence  of  green  among  internal  feeding  larvae, 
while  the  number  of  arboreal  feeders  so  coloured  is 
legion.  This  cause  of  colour  certainly  suffices  in 
many  transparent  caterpillars.  But  in  other  cases  the 
adjustment  arises  from  something  very  different, — in 
fact  the  larvae  are  affected  by  the  colour  of  the 
leaves  as  surroundings,  and  not  by  the  leaves  as  food. 
Having  regard  to  the  experiments  on  pupae,  Mr. 
Poulton  considers  it  probable  that  reflected  light 
influences  the  skin. 

The  investigations  which  he  undertook  in  proof  of 
this  were  laborious,  and  very  numerous.  Leaves 
were  sewn  together,  so  that  the  larvae  were  exposed 
to  the  upper  or  the  under  side  alone,  although  they 
ate  the  same  leaf  in  both  instances.  The  '  bloom  ' 
was  removed  from  the  under  sides  of  some  leaves, 
while  some  were  left  normal.  The  results  pro- 
claimed the  surroundings  and  not  the  food  to 
be  the  influencing  agent.  Species  of  Geometrae 
were  the  subjects  of  trial.  Larvae  were  selected 
which  resemble  the  twigs  or  bark  of  their  food-plant. 
Some  were  surrounded  solely  by  the  leaves  upon 
which  they  fed,  and  by  white  or  green  sur- 
faces ;  in  other  cases  numbers  of  dark  twigs  were 
mixed  with  the  leaves  of  the  food-plant.  In  the 
former  experiments  the  majority  of  the  larvae  be- 
came very  light  brown  or  light  gray  in  colour,  and 
quite  different  from  the  darker  larvae  of  the  same 
kinds  which  were  produced  when  the  latter  test  was 
resorted  to.  Mr.  Poulton  points  out  that  the  change 


240          ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

is  protective,  because  the  lighter  larvae  were  far  better 
concealed  on  the  green  leaves  and  stems  than  the 
darker  ones  would  have  been.  There  are  species  in 
which  the  larvae  become  green  when  they  are  reared 
among  green  shoots  and  leaves,  so  that  the  con- 
cealment is  wonderfully  perfect  (see  Figs.  46  and  47). 

It  is  a  still  more  interesting  fact  that  the  cater- 
pillars of  certain  species  can  adjust  the  colour  of 
their  cocoon  to  the  environment.  Of  this  class  of 
Variable  Protective  Resemblance  little  is  known. 
The  stimulus  of  surrounding  colour  surely  makes  itself 
felt  on  the  larva,  and  probably  the  effects  are  pro- 
duced through  the  medium  of  the  nervous  system. 
The  power  of  colour  variation  in  perfect  insects  as  the 
result  of  a  stimulus,  in  correspondence  with  the  pre- 
vailing tint  of  the  district,  also  awaits  investigation. 

The  cases  of  ordinary  protective  resemblance,  as 
we  have  seen,  can  be  well  explained  by  the  operation 
of  natural  selection.  Given  the  rudest  resemblance 
to  their  surroundings  in  the  first  place,  those  insects 
which  best  possessed  this  qualification  even  in  the 
most  minute  degree,  would  tend  to  escape  de- 
struction, and  their  less  fortunate  fellows  would  fall 
victims  to  their  foes.  Generation  after  generation 
this  selecting  action  would  continue,  until  those  most 
wonderful  appreciable  disguises  imitative  of  a  leaf  or 
some  such  object  had  been  built  up  and  perpetuated. 
Indefinite  variation  is  controlled  by  natural  selection, 
and  heredity  is  an  important  element.  It  is  to  be 
observed  that  no  explanation  is  given  of  the  cause  of 
the  original  variations  in  the  colour  of  the  insects,;  in 
a  word,  no  explanation  is  offered  of  the  origin  of 


VI          DEFENCES  OF  INSECTS          241 

colour.  Some  authorities  have  believed  that  we  find 
in  colour  a  result  attributable  to  the  direct  influence 
of  surroundings  accumulated  through  heredity.  The 
preceding  experiments  on  Variable  Protective  Re- 
semblance showed  the  medium  of  the  nervous  system 
to  be  indispensable,  so  that  the  results  are  indirect. 

It  must  not  be  thought,  however,  that  variable 
protective  resemblance  is  yet  in  part  due  "  to  the 
accumulation  through  heredity  of  the  indirect  influence 
of  environment  working  by  means  of  the  nervous 
system."  J  The  power  of  adjustment  of  colour  pos- 
sessed by  each  insect  is  essentially  adaptive.  Bias  to 
particular  colour  through  the  influence  of  ancestors 
would  at  once  weaken  the  efficacy  of  the  property, 
inasmuch  as  different  individuals  are  likely  to  meet 
with  different  environments.  But  here  also,  as  in  all 
other  cases,  the  power  is  to  be  explained  by  the 
operation  of  natural  selection.  The  primary  varia- 
tions are  controlled  and  quickened  by  it.  Its  function 
is  to  take  advantage  of  a  faculty,  regardless  of  the 
manner  in  which  it  originates  and  at  what  period  of 
the  insect's  life  the  change  is  induced.  The  power  of 
changing  colour  is  beneficial  to  the  insects  that  pos- 
sess it, — this  few  naturalists  will  deny.  It  follows 
that  natural  selection  will  produce  and  maintain 
the  power,  that  it  will  eliminate  any  variations,  or, 
to  express  it  differently,  that  it  will  eliminate  indi- 
viduals which  tend  to  depart  from  this  useful 
capacity. 

1  Poulton. 


R 


CHAPTER  VII 

DEFENCES  OF  INSECTS  OR  PROTECTION  AS  DERIVED 
FROM  COLOUR  (continued] 

A  conspicuously  coloured  group— Objection  to  colour — Different 
modes  of  insects  of  maintaining  existence  ;  possession  of 
nauseous  properties,  irritating  hairs  and  spines,  the  sting, 
hardness  of  substance,  wonderful  vitality,  capacity  for 
increase,  attitudes — Association  of  bright  colour  with  dis- 
tasteful qualities — Bright  colour  as  a  warning  ;  its  value — 
Various  combinations  of  means  of  defence — Resemblance 
between  Warning  Colours  and  patterns  ;  determining  causes 
of  the  repetition — Distinction  between  Warning  Colours  and 
those  produced  by  courtship — Sexual  colouring  made  use 
of  for  warning  ;  its  similarity — Conspicuous  and  nauseous 
but  non-vital  parts — One  meaning  of  broad  expanse  of  wing 
of  showy  butterflies — Mimicry — Bates  first  to  explain  the 
facts — Butterflies  that  are  objects  of  mimicry  in  tropics — 
their  unpalatability  indicated  by  conspicuousness  and 
abundance— True  Mimicry  as  distinct  from  all  warning 
appearances — The  term  mimicry — Mimicry  a  phase  of 
Protective  Resemblance — Mimicry  of  American  butterflies, 
of  the  Asiatic,  of  the  African,  in  British  Lepidoptera — 
Especially  prominent  in  female  ;  interpretation  of  pheno- 
menon— Affords  confirmation  of  theory  that  Mimicry  is 
produced  by  natural  selection — "  External  conditions," 
"  heredity  " — An  explanation  of  sexual  difference  of  form 


CH.  vii  DEFENCES  OF  INSECTS  243 

and  colour— Mimetic  analogies  among  beetles — Hymen- 
optera  mimicked  by  Lepidoptera,  •  Diptera,  Coleoptera, 
Orthoptera,  Hemiptera — Mimicry  of  Coleoptera — Of  ants 
by  spiders — Of  vertebrates — Predacious  insects  that  re- 
semble their  prey,  or  a  form  to  which  their  prey  is  in- 
different— The  great  frequency  of  Mimicry  in  insects. 

Apart  from  the  insects  considered  in  the  last  chapter, 
in  whose  lives  the  principles  of  disguise  and  conceal- 
ment constitute  so  important  a  feature,  the  most 
casual  observer  of  Nature  must  be  struck  by  the 
existence  of  a  group  in  whom  the  development  of 
brilliant  colour  and  conspicuousness  is  as  marked  as 
are  the  suppression  and  absence  of  these  properties  in 
the  previous  cases.  The  latter  court  observation 
and  proclaim  their  presence  ;  to  elude  notice  every 
imaginable  contrivance  seems  as  it  were  to  be  exerted 
by  the  former  class.  In  face  of  the  remarkable 
utility  of  the  assumption  of  obscure  or  imitative  tints 
by  all  animals,  and  the  readiness  of  the  acquisition 
of  means  of  concealment  through  the  agency  of 
natural  selection,  it  would  appear  that  there  ought 
to  be  no  conspicuous  and  brilliantly  coloured  insects. 

Where  Protective  Resemblance  is  wanting,  the  idea 
instantly  suggests  itself  that  protection  must  be 
gained  in  some  other  way.  Observation  of  the  life  of 
insects  soon  shows  that,  far  from  being  confined  to 
one  mode  of  maintaining  their  existence,  they  are  in 
fact  possessed  of  a  variety  of  means  by  which  to 
defend  themselves  from  enemies  and  to  obtain  their 
food. 

All  are  not  equally  palatable  to  insect-eating 
animals.  Experiment  places  it  beyond  doubt 

R  2 


244          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

that  many  possess  some  unpleasant  quality,  or 
qualities,  rendering  them  if  caught  unfit  for  food,  or 
even  disgusting  or  dangerous.  A  widely-extensive 
group  is  repugnant,  and  is  constantly  refused,  owing 
to  their  possession  of  a  more  or  less  powerful  and 
revolting  taste  or  smell.  Almost  every  order  furnishes 
instances  of  defensive  scents,  but  few  yield  individuals 
more  notoriously  bad  in  this  respect  than  the 
Coleoptera,  Orthoptera,  and  Hymenoptera.  Among 
Lepidoptera,  numbers  of  the  larvae  prove  distasteful. 
The  chrysalis  of  the  Magpie  Moth  (Abraxas 
grossulariatd],  and  many  butterflies  and  moths  are 
similarly  defended.  In  some  cases  an  offensive  odour 
is  emitted  at  pleasure  from  particular  organs.  The 
peculiar  faculty  of  the  so-called  Bombardier  Beetles, 
consisting  in  the  discharge  of  a  volatile  liquid  like  a 
puff  of  smoke,  accompanied  by  a  distinct  crepitating 
explosion  and  attended  by  a  disagreeable  scent,  is 
well  known.  An  enemy  in  pursuit  is  dismayed,  and 
arrested  on  its  progress,  enabling  the  beetle  to  gain 
time,  and  probably  to  effect  its  escape.  Emission  of 
strongly  smelling  fluids  on  the  approach  of  an  enemy 
is  by  no  means  unusual.  The  larvae  of  certain 
Sawflies  (Hymenoptera}  have  a  number  of  odoriferous 
glands  along  the  middle  of  the  ventral  surface,  more- 
over these  insects  are  gregarious,  collecting,  often 
a  hundred  and  more,  on  the  branches  of  trees  which 
they  completely  denude.  In  the  event  of  one  of 
the  larvae  being  touched  or  disturbed,  it  instantly 
gives  forth  a  drop  of  a  clear  resinous  liquid  from  its 
glands,  and,  what  is  still  more  remarkable,  all  its 
neighbours,  as  though  moved  by  an  impulse  in  com- 


vii  DEFENCES  OF  INSECTS  245 

mon,  do  the  same,  a  combination  of  forces  which 
diffuses  an  atmosphere  around  the  company  probably 
effective  in  warding  off  most  enemies.  Lady-birds 
(Coccinella)  can  eject  nauseous  fluids,  as  can  numerous 
caterpillars.  Offensive  watery  drops  may  likewise  be 
caused  to  issue  from  the  bodies  of  Lepidoptera  in 
their  perfect  state. 

Caterpillars   may   be  protected  by   the  possession 
of  hairs,   which    would   appear    capable    of   causing 
extreme    discomfort    on     the    delicate    skin    of  the 
mouth.     Many  persons  know  how 
great  can  be  the  annoyance  ex- 
perienced   in    handling    some    of 
these  hairy  larvae.    The  hairs  shed 
will  sometimes  produce  inflamma- 
tion or  a  rash  on  the  hands,  or  on 
the    face    or    neck,     should     the 
operator  happen  to  touch   these 

,  ...  FIG.  48.— The  larva  of  Buff- 

more  sensitive  parts  when  getting      tip  Moth  (pyg<era  buce- 

.  ,  r         1  .  ,  .    ,  phala),    a    caterpillar  with 

rid       Of      the        minute       hairS      With         Warning    Colours     and    a 

•  •    i         i  •         «  i  ,          nauseous  taste;  from  Curtis. 

which  his  hands  are  covered. 
There  is  experimental  proof  that  such  larvae  are 
regarded  with  aversion.  Some  animals  positively 
refuse  to  touch  them,  others  may  seize  them,  and 
will  afterwards  relinquish  them  with  every  sign  of 
dislike  and  irritation.  If  to  birds  the  hairy  covering 
is  much  less  unpleasing,  it  may  still  be  the  means  of 
the  escape  of  the  possessor  from  these  enemies. 
When  disturbed  the  caterpillar  of  the  Great  Tiger 
Moth,  which  is  beset  with  long  dense  hairs,  usually 
rolls  itself  up  into  a  round  ball,  and  is  then  taken  by 
a  bird  with  great  difficulty,  judging  by  its  tiresome 


246          ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

liability  to  glide  from  between  one's  fingers.  Spines 
and  tubercular  prominences  are  likewise  present  on 
many  caterpillars,  rendering  them  uncomfortable,  and 
maybe  painful  morsels  to  assailants.  Hairs  or  spines, 
however,  defend  certain  species  by  contributing 
towards  the  production  of  striking  protective  resem- 
blance. 

The  sting  possessed  by  the  females  of  many 
Hymenoptera  is  a  defensive  attribute  that  keeps  man 
himself  at  bay.  Obviously  it  must  enable  these 
insects  to  enjoy  considerable  immunity  from  attack. 

Hardness  of  substance  of  external  parts  is  probably 
also  protective.  The  elytra  of  beetles  are  often  so 
impenetrable  as  to  be  most  difficult  to  pin,  and  the 
golden  wasps  (Chrysididce)  which  do  not  sting,  have 
as  a  substitute  the  power  of  rolling  themselves  up 
into  a  ball,  which  is  almost  as  firm  and  polished  as 
though  it  were  made  of  metal.  Insects  thus  endowed 
must  form  exceedingly  unpleasant  and  indigestible 
fare,  and  will  be  disregarded  by  insect-eating  animals 
unless  sore  pressed  by  want  of  food. 

In  remarkable  vitality  insects  have  another  means 
of  defence.  Their  capacity  for  increase  in  other  cases 
is  so  great  that,  notwithstanding  the  destruction  of 
the  adults  to  any  number,  ample  provision  seems 
always  to  exist  for  the  continuance  of  the  race. 
Again,  some  attitudes  are  protective,  such  as  the 
simulation  of  death,  or  a  terrifying  posture  may  be 
assumed,  so  as  to  inspire  alarm  and  repel  the  enemy. 

Insects  defended  by  some  of  these  kinds  of  protec- 
tion in  a  high  degree  are  free,  so  to  speak,  to  develop 
Colour,  for  sexual  purposes  probably,  and  for  the 


vii  DEFENCES  OF  INSECTS  247 

varied  uses  to  which  colour  may  be  put  among 
animals  ;  or  it  would  be  more  correct  to  say  that,  some 
of  these  defences  being  adopted,  the  causes  which  lead 
to  the  development  of  colour  have  been  enabled  to  do 
their  work  unchecked.  It  can  easily  be  understood 
how  such  defence  may  be  in  a  measure  so  perfect  as 
to  be  adequate  for  all  the  wants  of  the  race,  and 
ensure  the  maintenance  of  large  numbers,  in  which 
case  the  suppression  of  colour  is  no  longer  necessary, 
and  gorgeousness  may  be  developed  without  harmful 
effect.  Hence  among  insects  best  protected  in  the  ways 
described  is  found  the  greatest  amount  of  colour,  or  at 
any  rate  little  or  no  attempt  at  protective  resemblance. 
To  give  only  one  example,  the  common  wasp,  the 
hornet,  and  many  humble-bees  which  are  armed  with 
a  formidable  sting,  are  all  conspicuous,  and  not  one 
of  the  stinging  Hymenoptera  is  coloured  to  resemble 
an  inanimate  or  vegetable  object. 

Bright  colour  is  not  only  developed  for  sexual  and 
like  purposes  ;  paradoxical  as  it  seems,  it  may  be 
of  high  protective  value.  It  acts  as  a  danger-flag,  a 
warning  to  enemies  that  the  possessor  is  inedible. 
This  may  at  first  appear  to  be  an  advantage  to  the 
enemies  rather  than  to  the  conspicuous  forms,  and  so 
militates  against  accounting  for  the  rise  and  growth  of 
the  character  by  the  action  of  natural  selection,  for 
natural  selection  cannot  possibly  produce  any  modi- 
fication intended  exclusively  for  the  good  of  another 
species.  But  the  conspicuous  insect  is  benefited  by 
its  gaudy  colour.  It  is  at  once  recognised  as 
distasteful,  and  is  unmolested.  Had  it  resembled 
its  surroundings  it  would  have  been  liable  to  be 


248          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

seized  and  tasted,  and  though  it  was,  afterwards 
rejected  in  all  probability  the  wounds  would  prove 
ultimately  fatal.  Thus  by  natural  selection  have 
the  bright  colouration  and  the  distasteful  qualities 
become  associated.  The  association  is  one  easily 
learned  and  remembered  by  enemies,  and  saves  a 
continual  destruction  of  individuals.  The  immensity 
of  the  benefit  derived  by  the  conspicuous  species  is 
realised  when  it  is  considered  how  small  is  the 
comparative  loss  of  life  involved  in  the  education  of 
the  enemy. 

Let  it  not  be  supposed  that  these  varied  means  of 
protection  are  necessarily  attended  by  Warning 
Colours.  Nature  is  open  to  too  many  influences  to 
be  able  to  develop  on  any  such  rigid  hard  and  fast 
plan.  Here  we  find  one  set  of  defences  in  combina- 
tion, there  another.  The  gregarious  habit  of  some 
inedible  dull-coloured  caterpillars  is  of  itself  a 
"  warning,"  for  their  offensive  odour  gives  timely 
notice  to  an  approaching  enemy,  so  that  the  acquisi- 
tion of  bright  colour  can  be  dispensed  with.  Again 
the  great  family  of  ground-beetles  (Carabidse)  are 
almost  all  of  disagreeable  smell,  but  they  do  not 
present  very  vivid  hues,  probably  because  they  are 
mostly  nocturnal  and  predacious,  and  it  is  important 
that  they  should  be  sufficiently  invisible  at  night  to 
creep  unseen  upon  their  prey.  By  day  their  odour 
and  taste  keep  foes  at  a  distance,  while  the  metallic 
tints  adorning  them,  when  they  arc  not  wholly  black, 
are  fairly  conspicuous.  It  must  be  remembered  that 
the  acquisition  of  an  unpleasant  quality  must  precede 
the  appearance  of  warning  colour.  The  properties  that 


DEFENCES  OF  INSECTS 


249 


are  most  commonly  accompanied  by  warning  colours 
are  those  of  bad  taste  or  smell  (see  Fig.  48),  attributes 
the  possession  of  which  it  is  a  matter  of  great  con- 
sequence to  the  solitary  individual  to  conspicuously 
advertise.  It  should  perhaps  be  mentioned  that  there 
are  many  cases  where  brilliant  colour  has  not  been 


FIG.  49.— Homeland  Mimetic  Bug;    rom  Belt. 

experimentally  shown    to   be   associated  with    some 
distasteful  property. 

Where  colour  serves  to  proclaim  danger  or  in- 
edibility, it  is  an  interesting  fact  that  the  signal  is  a 
very  constant  one.  The  colours  that  are  chiefly 
acquired  by  nauseous  insects  are  those  that  produce 
the  sharpest  contrasts,  therefore  they  are  the  most 
easily  perceived,  indeed  they  obtrude  themselves 
upon  notice,  and  their  number  being  small  the  same 


250          ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

combinations  are  inevitably  repeated  again  and  again, 
and  by  insects  of  widely  different  families.  Similarly 
the  patterns  that  are  employed  are  few  and  pre- 
eminently conspicuous  and  simple.  In  this  manner 
insect-eating  animals  are  not  only  readily  attracted 
to  the  signal,  they  early  and  quickly  recognize  un- 
palatability  or  danger  as  a  whole,  and  probably  have 
not  to  gain  experience  through  trial  of  every 
nauseous  species  in  their  locality,  an  education  that 
would  be  unpleasant  and  tiresome  to  the  eaters  and 
costly  of  life  to  the  insects  tested.  The  frequent 
repetition  of  the  same  colours  and  patterns  in 
distasteful  forms  is  a  necessity,  since  only  a  limited 
number  afford  the  required  effect,  and  the  repetition 
is  itself  an  advantage,  and  consequently  has  been 
encouraged  by  natural  selection.1 

It  would  appear  to  be  a  difficult  matter  to 
distinguish  which  are  Warning  Colours.  Probably 
all  ornament  in  mature  individuals  may  be  partly 
attributed  to  the  agency  of  sexual  selection,  and  has 
a  sexual  interpretation.  But  generally  speaking  it  is 
easy  to  distinguish  the  appearance  which  has  a  purely 
sexual  meaning,  and  that  which  has  been  specially 
modified  for  other  uses  as  well.  The  colours  pro- 
duced by  courtship  are  beautiful,  more  or  less 
blended,  the  patterns  are  elegant,  whereas,  as  we  have 
seen,  startling  and  strongly  contrasted  colours  and 
primitive  patterns  are  evidences  of  the  warning 
signal;  intrinsic  beauty  gives  way  before  conspicuous- 
ness  and  effect.  But  besides  these  differences,  the 
particular  value  of  colour  may  be  judged  by  the 
1  Poulton. 


vii  DEFENCES  OF  INSECTS  251 

extent  of  its  distribution  over  the  body  of  the 
animal.  If  the  colour  is  widespread,  and  cannot  be 
veiled  during  the  period  of  rest,  then  it  proclaims 
itself  to  be  in  most  part  of  warning  significance. 
When  it  is  of  importance  for  warning,  no  care  is 
taken  to  hide  it,  and  the  flight  is  slow,  so  that  the 
adornment  is  completely  displayed.  Where  the 
appearance  has  a  sexual  value  alone  the  insect 
mounts  zealous  guard  over  it  for  the  especial  purpose 
of  courtship.  The  flight  then  is  swift  and  wary, 
and  a  characteristic  habit  is  to  settle  with  sudden 
abruptness. 

These  two  groups  nevertheless  pass  into  each  other, 
especially  in  the  Tropics,  where  colours  which  strictly 
are  produced  by  courtship  seem  to  be  utilised 
for  warning  purposes.  In  such  cases  the  dis- 
tribution of  colour  becomes  more  general,  and  the 
habits  indicative  of  nauseous  species  are  assumed. 
When  warning  appearance  has  been  developed  by 
this  method,  the  colours  and  patterns  of  the  members 
of  each  of  the  groups  distinctly  resemble  each  other, 
with  the  same  good  results  as  when  the  similarity 
in  the  warning  colouration  has  arisen  differently. 

The  resemblance  between  certain  species  of  un- 
palatable insects  is  such  that  they  may  be  said  to 
mimic  each  other.  This  fact  was  first  observed  by 
Bates,  and  Fritz  Mliller  explains  it  to  be  to  the  advan- 
tage of  both  species,  seeing  that  the  destruction  of 
life  involved  in  the  education  of  their  enemies  is  shared, 
and  so  falls  less  seriously  on  each  independently- 
These  remarkable  resemblances  are  comparatively 
rare,  but  Professor  Meldola  applies  the  same  explana- 


252          ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

tion  to  the  general  similarity  which  prevails  throughout 
immense  numbers  of  species  in  these  protected  groups. 
In  many  cases,  the  species  in  each  group  are  closely 
related,  but  in  some  instances  the  similarity  has 
arisen  between  species  belonging  to  very  different 
groups.  The  resemblance  of  the  Danaids  of  tropical 
America  to  the  Heliconias  of  the  same  localities 
probably  constitute  a  most  interesting  example  of 
similarity  of  forms  which  were  originally  unlike. 
These  Heliconoid  Danaids,  as  they  are  called,  have 
acquired  in  a  wonderful  manner  the  colours  and  wing- 
shape  of  their  models  the  Heliconias,  and  are  distinct 
from  all  the  other  ^members  of  the  group.  The  ad- 
vantage derived  is  mutual,  for  their  enemies  have  to 
learn  only  one  type  of  colouring  and  form  and  but  the 
same  motion  in  flight 

Obviously  the  advantage  leans  greatly  to  one  side 
where  of  a  group  protected  by  corresponding  colours 
and  patterns  certain  of  the  number  are  possessed  of 
comparatively  less  unpleasant  attributes,  an  imper- 
fection that  they  effectively  hide  under  the  more 
complete  protection  of  the  species  resembled. 
Although  these  resemblances  contain  in  them  an 
element  of  true  Mimicry,  and  reap  some  of  its 
advantages,  they  must  be  distinguished  from  that 
principle.  Those  cases  where  the  mimicking  and  the 
mimicked  species  cannot  be  said  to  differ  as  regards 
their  unpleasant  qualities  approach  less  near  to  true 
Mimicry. 

Warning  colour  and  conspicuonsness  may  protect 
the  forms  developing  them  in  another  fashion. 
Attention  is  directed  to  some  unimportant  part, 


vii  DEFENCES  OF  INSECTS  253 

which  is  highly  nauseous.  If  the  structure  is  seized 
by  the  enemy,  and  apparently  it  is  a  most  convenient 
point  to  capture,  it  breaks  off  without  harm  to  the 
owner,  but  with  such  uncomfortable  effects  on  the 
attacking  animal  that  the  former  probably  escapes 
unhurt. 

In  other  cases,  a  non-vital  part  is  particularly 
attractive  but  is  unattended  by  unpleasant  qualities. 
The  part  gives  way  upon  seizure,  so  that  the  insect 
is  afforded  a  chance  of  escape.  This  is  probably  a 
meaning  of  the  broad  expanse  of  wing  of  many 
weak-flying  butterflies,  and  of  their  bright  colouration 
irrespective  of  its  pronounced  sexual  utility.  Such 
butterflies  are  tolerably  plentiful,  poor  as  one  might 
deem  their  opportunities  for  existence  and  increase. 
But  specimens  are  often  taken  with  pierced  and 
broken  wings,  as  though  they  had  been  caught 
and  had  escaped.  Wings  that  were  less  showy  in 
flight  would  not  have  constituted  so  good  a  target, 
and  had  they  been  smaller  in  proportion  to  the  body 
the  enemy  would  have  been  more  likely  to  hit  upon 
a  vital  spot.  Where  the  butterfly  is  active,  and  has 
well  developed  protective  tints,  its  brilliant  colour — 
leaving  the  greater  sexual  use  out  of  the  question 
— serves  as  protection  in  reserve  after  its  other 
defences  have  broken  through,  and  attracts  enemies 
to  some  feature  of  no  importance,  when  it  has  failed 
to  elude  its  pursuer  either  by  its  swiftness  or  by  its 
disguise.  This  colour  differs  from  Warning  Colour 
proper.  It  is  associated  with  protective  tints,  and 
the  enemy,  although  it  makes  a  mistake,  is  un- 
affected by  disgust  or  danger. 


254          ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

We  now  come  to  one  of  the  most  interesting 
aspects  of  our  subject,  to  one  the  discovery  of  which 
admitted  of  our  understanding  many  of  the  phenomena 
that  have  gone  before.  Entomologists  have  been  long 
aware  that  certain  butterflies  belonging  to  widely 
separated  groups  possess  a  strange  close  superficial 
resemblance  in  shape  and  colour,  a 
resemblance  in  external  parts  but  not 
in  essential  internal  structure,  a  re- 
semblance that  deceives,  while  natu- 
rally  the  mimicking  forms  are  unlike 
those  with  which  they  have  any  real 
affinity.  The  facts  were  familiar,  but 
no  adequate  explanation  was  forthcoming,  they  were 
simply  regarded  as  curious  and  inscrutable  until  1862. 
In  that  year  Mr.  Bates'  wonderful  memoir  of  the 
Lepidoptera  of  the  Amazon  Valley  solved  the  problem 
which  had  been  so  long  a  puzzle,  and  gave  impetus  to 
kindred  investigation  among  groups  of  the  Insecta 
other  than  the  Lepidoptera.  Mr.  Bates  showed  the 
advantage  that  must  be  gained  by  a  palatable  and 
nonprotected  and  hunted  form  if  it  imitated  the  con- 
spicuous outward  dress  and  habits  of  a  species,  of 
whose  inedibility  these  habits  and  conspicuousness 
were  certain  tokens,  and  effectual  safe-guards  against 
persecution  and  diminution  of  its  numbers.  The 
cause  of  the  existence  of  brilliant  colour  in  butterflies 
possessed  of  some  attribute  unpleasant  to  their  enemies 
being  thus  clearly  recognised^  it  was  soon  seen  that 
the  same  explanation  applied  to  many  other  groups. 

The  butterflies  which  are  the  objects  of  Mimicry 
belong  chiefly  to  the  -two  great  families  Danaidae  and 


vii  DEFENCES  OF  INSECTS  255 

Acraeidse.  They  comprise  many  hundreds  of  species, 
and  inhabit  all  the  warmer  parts  of  the  world.  The 
Heliconidae  of  tropical  America  are  likewise  mimicked. 
These  butterflies  are  generally  large,  conspicuously 
and  even  gorgeously  coloured,  and  their  flight  is  feeble 
and  slow.  There  is  not  only  disregard  of  concealment 


FIG.  51. — An  ant-like  Spider  (Synemosy  no,  formica)  ',  from  Peckham. 

when  on  the  wing,  in  rest  no  protective  tints  are 
shown, 'and  both  surfaces  of  the  wings  are  equally 
conspicuous.  The  abundance  of  individuals  is  also 
striking.  These  are  characteristics  indicating  un- 
palatability,  which  affords  the  butterflies  immeasur- 
able pre-eminence  over  their  fellows  in  immunity 
from  attack,  depending  upon  the  effectiveness  of 
their  colour  and  habits  to  give  ready  warning 
of  the  circumstance.  All  observers  speak  of  their 
peculiar  and  often  powerful  pungent  odour,  and  it  has 
been  noticed  that  they  are  constantly  neglected  and 
refused  by  birds  of  many  kinds,  and  by  spiders, 
dragon-flies,  lizards,  and  monkeys,  although  all  these 
greedily  destroy  butterflies  which  are  much  less 
abundant,  and  which  are  swifter  and  less  easily 
captured.  The  facts  point  to  the.  possession  by  these 


256          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

favoured  races  of  a  distasteful  property,  which  appeals 
to  widely-separated  classes  of  insectivorous  animals. 
In  a  word  the  persecution  of  these  butterflies  seems  to 
have  almost  wholly  ceased,  so  that  the  advantage 
would  be  incalculable  of  being  mistaken  for  them  to 
species  less  specially  protected,  and  accustomed  to  be 
devoured.  That  the  mimickers  need  to  protect 
themselves  is  plainly  evident,  for  while  the  mocked 
forms  abound,  almost  always  in  literal  swarms,  an 
incontestable  proof  of  their  general  exemption  from 
destruction,  the  mockers  are  often  rare  insects,  and 


FIG.  52.— Adult  Caterpillar  of  the  Large  Elephant  Hawk  Moth  (Chterocatnpa 
elpenor)  when  undisturbed  ;  from  Weismann. 

belong  to  rare  groups,  witness  equally  undeniable  of 
their  habitual  exposure  to  danger.  The  latter  appear 
to  be  really  eatable,  and  elude  their  foes  solely  by 
their  counterfeit  of  the  facies*  of  uneatable  and  well- 
protected  species  of  the  same  locality,  an  imitation 
such  as  to  deceive  the  eyes  of  predacious  birds  and 
insects. 

It  will  be  observed  that  Mimicry  aims  at  the 
acquisition  of  Warning  Colours.  True  Mimicry  is 
quite  distinct  from  all  warning  appearances,  although 
a  gradual  transition  to  it  .from  the  latter  may  be 
traced.  In  the  close  resemblance  and  imitation 


vii  DEFENCES  OF  INSECTS  257 

between  specially  protected  species,  even  between 
most  distantly  related  groups,  the  similar  forms 
possess  nauseous  attributes,  although  they  may 
possess  them  more  or  less  completely.  But  in 
Mimicry  the  mimicking  species  are  entirely  wanting 
in  unpleasant  properties,  they  exist  by  deceptively  as- 
suming the  appearance  of  forms  in  which  such  pro- 
tection is  strongly  marked.  In  the  former  cases 
the  warning  colour  always  acts  its  own  true  part.  It 
is  an  indication,  as  effectual  as  possible,  a  warning 
to  enemies  of  real  inedibility  or  danger.  As  regards 
true  Mimicry,  so  far  as  the  unprotected  mimickers  are 


FIG.  53. — Dorsal  view  of  the  caterpillar  of  the  Small  Elephant  Hawk  Moth 
(Chcerocampa  porccllns)  in  its  alarming  attitude;  the  posterior  "eyes"  are 
inconspicuous  in  this  species  ;  from  Weismann. 

concerned  it  is  a  false  signal,  a  proclamation  of  a  bad 
quality  which  has  no  existence  .in  fact. 

Mimicry  is  an  essentially  appropriate  term  for  that 
which  it  is  intended  it  should  designate.  It  implies 
deception,  mere  imitation,  a  copy,  unreality,  and  this 
is  exactly  the  character  of  the  resemblances  of  the 
unprotected  forms  in  this  class  of  cases.  Exception 
has  been  taken  to  the  word,  because  it  is  ordinarily 
used  in  the  sense  of  voluntary  imitation,  and  of 
course  the  mimicry  here  alluded  to  is  not  of  a  con- 
scious nature.  Hardly  anyone  will  go  so  far  as  to 
believe  that  the  actual  volition  of  the  insects  has 

s 


258          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

been  in  any  way  concerned  in  the  production  of  these 
remarkable  mimetic  analogies.  It  is  true  the 
mimicker  often  copies  the  mimicked  in  flight,  and  in 
other  habits.  But  this  has  probably  arisen  in  precisely 
the  same  manner  as  the  imitation  of  colour  and  form, 
by  the  gradual  operation  of  natural  selection,  which 
generation  after  generation  would  tend  to  preserve 
the  individuals  whose  flight  best  resembled  that  of  the 
model,  just  as  it  preserved  those  whose  form  and 
colour  most  closely  approached  those  qualities  in  the 
imitated  insects.  The  less  perfect  degrees  of  resem- 
blance would  be  gradually  eliminated,  and  only  the 
others  left  to  propagate  their  kind.  The  meaning 
expressed  is  the  same  in  effect  as  voluntary  actions, 
and  in  this  sense  alone  the  term  Mimicry  was  adopted 
by  Mr.  Bates. 

Plainly  Mimicry  is  in  reality  a  very  important  phase 
of  special  protective  resemblance,  it  is  an  adaptation  of 
precisely  the  same  nature.  In  the  one  case  an  insect 
gains  advantage  by  superficial  imitation  of  a  vegetative 
or  some  inanimate  object,  in  Mimicry  the  animal  is 
benefited  by  superficial  resemblance  to  another  living 
insect.  But  while  in  ordinary  protective  resemblance 
the  simulated  appearance  is  used  for  concealment,  in 
the  case  of  mimicry  its  purpose  is  to  attract  attention. 
The  causes  involved  in  the  production  of  the  two 
phenomena  are  identical.  They  are  the  selecting 
agency  of  natural  selection,  the  law  of  the  survival 
of  the  fittest,  or  the  preservation  of  favoured  races  in 
the  struggle  for  life. 

In  tropical  America,  the  Heliconidae  and  the 
Danaidae  which  resemble  them  are  mimicked  chiefly 


vil  DEFENCES  OF  INSECTS  259 

by  Pieridae  (Leptalis),  which  are  quite-  distinct  from 
their  models  in  structural  characteristics.  The 
Pieridae  is  the  family  to  which  our  common  Garden 
Whites  or  Cabbage  Butterflies  belong.  Like  the 
specimens  at  home  non-mimetic  species  of  South 
America  are  white,  and  to  these  the  mimetic  *  Pieridae 
present  a  striking  contrast.  Different  species  imitate 
those  of  the  Heliconidae  of  the  same  district  in  the 
form  of  the  wings,  every  shade  of  colour  and  pattern 
is  copied,  the  imitation  being  carried  out  to  such  a 
wonderful  degree  as  to  continually  deceive  the  eyes  of 
the  most  experienced  collectors.  The  mocking  species 
and  the  forms  mocked  usually  fly  in  the  same  part  of 
the  forest,  and  generally  in  company,  to  the  evident 
advantage  of  the  Leptalis.  And  as  if  to  derive  all 
possible  benefit  from  the  association,  the  mimicking 
Pieridae  are  extremely  scarce,  while  the  Heliconidae 
are  very  common,  so  that  it  seems  hardly  possible  for 
an  enemy  to  detect  the  fraudulent  insects,  or  that  it 
would  take  the  trouble  to  detect  them,  even  were  it 
aware  of  their  presence.  The  excessive  abundance  of 
the  mimicked  butterflies  wherever  they  occur,  indicates 
the  antiquity  and  the  specially  protected  nature  of 
the  species,  and  is  exactly  the  characteristic  to  induce 
the  resemblance. 

Besides  the  Pieridae,  a  genus  of  quite  another  family 
of  pretty  little  American  butterflies  (Erycintdce)  mimic 
the  specially  protected  and  dominant  forms.  The 
Swallow-tails  (Papilio),  and  others,  and  certain  genera 
of  diurnal  moths  likewise  present  species  which  often 
copy  the  same  favoured  creatures.  It  sometimes 
occurs  in  a  district,  that  a  species  of  Leptalis  species 

S  2 


260          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

of  two  other  genera  and  a  moth  will  all  be  found 
mimicking  the  same  Ithomia. 

The  black  and  red  section  of  South  American 
Papilios,  and  a  genus  of  Erycina  are  themselves  in  a 
less  degree  the  objects  of  imitation. 

In  the  Malayan  Isles  and  in  India,  the  Danaidae, 
which  are  the  representatives  of  the  Heliconidae  in  the 
Old  World,  seem  to  be  the  chief  models  for  Mimicry. 
Papilios  in  many  cases  are  the  mimicking  species, 
taking  as  their  copies  different  species  of  Euplcea.  On 
the  other  hand  some  Papilios  are  mimicked. 

Parallel  series  of  imitation  in  the  Lepidoptera  of 
Africa  have  been  described  by  Mr.  Roland  Trimen. 
Here  again  the  families  Danaidae  and  Acraeidae,  the 
last. of  which  have  their  metropolis  in  Africa,  are 
attended  by  their  mimics,  chiefly  Papilios  and  species 
of  Diadema,  a  genus  allied  to  our  own  peacock  and 
tortoiseshell  butterflies.  Many  Acraeidae  are  models 
for  Nymphalidae  and  Papilionidae.  Mr.  Trimen 
gives  a  list  of  no  fewer  than  ten  species  and  varieties 
of  Papilio,  and  sixteen  of  Diadema,  as  being  perfect 
mimics  of  Danais  or  Acraea  prevalent  in  the  same 
districts.  The  mimickers  constantly  accompany  the 
mimicked  forms,  and  sometimes  where  the  sexes  of 
the  latter  are  dissimilar  the  sexes  of  the  imitators  differ 
accordingly. 

Dr.  Wallace  believes  it  probable  that  we  find  a  case 
of  mimicry  among  British  Lepidoptera,  in  the  resem- 
blance of  the  female  of  the  Muslin  Moth  (Diaphora 
mendicd]  to  the  White  Ermine  Moth  (Sptlosoma 
menthastri).  The  latter  has  been  observed  to  be 
constantly  refused  by  young  turkeys,  and  by  bull- 


vii  DEFENCES  OF  INSECTS  261 

finches,  chaffinches,  and  other  birds  of  the  kind.  It  is 
thus  proved  to  be  unpalatable  to  them,  and  we  may 
conclude  that  it  is  exempt  from  all  attack,  which 
appears  very  likely  because  of  its  great  abundance 
and  its  conspicuous  white  colour.  The  moth  Dia- 
phora  occurs  about  the  same  time  of  year,  and  the 
female  alone  is  white.  It  is  much  like  Spilosoma, 
and  might  easily  be  mistaken  for  it  in  the  dusk,  while 
the  male  is  dark,  and  protectively  coloured,  so  that 
this  species  is  probably  palatable  ;  it  is  also  much  less 
common.  All  the  facts  point  to  the  female  Diaphora 


FIG.  54.— The  larva  of  Puss  Moth  (Centra  vinnla)  resting  ;  full  fed  ;  natural  size. 

being  a  mimic  of  Spilosoma,  standing  in  the  same 
relation  to  it  as  their  mimics  do  to  Heliconidae  and 
Danaidae.  Until  the  palatability  of  the  supposed 
mimic  is  proved,  however,  this  cannot  be  definitely 
advanced  as  an  instance  of  true  Mimicry,  and  must 
be  classed  among  the  close  resemblances  between 
unpalatable  forms  protected  by  Warning  Colours. 
The  affinity  between  the  two  species  will  likewise 
always  exclude  it  from  the  best  examples  of  mimicry, 
When  studying  mimetic  resemblances  among  but- 
terflies, the  conclusion  is  forced  upon  us  that  the 


262          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

mimickers  are  very  frequently  only  females,  the  males 
retain  more  or  less  the  appearance  of  their  immediate 
congeners.  In  several  species  of  South  American 
mimetic  '  Whites '  (Pieridce],  the  males  are  plain 
white  and  black,  or  a  portion  of  the  wings  is  so 
coloured,  it  is  the  females  that  present  rich  black  and 
red  and  yellow  hues,  barred  and  spotted  to  resemble 
the  Heliconidae.  These  mimicking  females  some- 
times associate  with  the  abundant  Heliconidae  in  the 
shades  of  the  forest,  their  white  males  frequent  open 
sunny  spots,  assembling  much  with  other  white  and 
yellow  butterflies  by  the  river  banks.  The  superiority 
of  the  female  in  the  acquisition  of  mimetic  tints  Dr. 
Wallace  ascribes  to  her  greater  need  for  protection 
than  the  other  sex.  Her  slower  flight,  the  necessity 
for  her  existence  until  she  has  sought  for  a  place  of 
safety  wherein  to  lay  her  eggs,  during  which  time  the 
prolonged  life  of  the  male  is  of  no  consequence  to  the 
continuance  of  the  race — all  point  to  the  comparative 
higher  importance  of  the  female  insect,  and  her  claim 
to  defence. 

Granting  this  interpretation  we  obtain  strong  con- 
firmation of  the  theory  of  Mimicry  as  offered  by  Mr. 
Bates,  and  wonderful  support  to  the  argument  that 
the  phenomenon  is  brought  about  by  natural  selection. 
Of  the  two  sexes  we  have  seen  that  one  requires  pro- 
tection most,  in  many  cases  it  is  that  one  which 
mimics  the  protected  forms,  while  the  other  whose 
need  is  less  is  frequently  non-mimetic.  It  is  therefore 
clear  that  Mimicry  has  arisen  through  necessity  for 
protection,  and  this  explanation  favours  the  claim 
that  Mimicry  is  produced  by  natural  selection. 


VII 


DEFENCES  OF  INSECTS 


263 


It  has  been  urged  that  mimetic  colouration  is  due  to 
"  external  conditions,"  since  female  Pieridae  are 
mimetic  of  the  Heliconidae  with  which  they  associate, 
while  their  males  whose  habits  are  different  are  non- 
mimetic.  The  fact  that  the  same  resemblances  occur 
where  the  two  sexes  are  alike  in  habit  and  fly  in  the 
same  localities,  entirely  disproves  this  theory.  Nor 
is  it  more  feasible  to  ascribe  to  "  heredity  "  or  rever- 
sion to  ancestral  types  a  resemblance  which  exists 
alone  in  one  of  two  sexes,  which  are  precisely  alike 
as  regards  heredity.  Mimicry  seems  to  be  intimately 
connected  with  the  well-being  of  the  mimicking 
species,  with  its  preservation,  its  direct  advantage  in 
the  struggle  for  existence. 

Mimicry  in  the  female  is  of  essentially  the  same 
nature,  and  due  to  the  same  cause  as  the  fact  of  the 
frequently  duller  tints  of  female  butterflies  as  com- 
pared with  the  males.  The  circumstance  of  the  highly 
specialised  forms  of  protec- 
tive resemblance  to  inani- 
mate objects  in  the  females 
of  other  orders,  whose  males 
show  only  a  very  rude 
approximation,  bears  the 
same  interpretation.  The 
female  is  the  sex  that  is 
disguised.  She  assumes  the 
general  quiet  tints  of  nature, 

or  she  adopts  the  exact  colour  and  form  of  a 
particular  vegetative  or  mineral  substance,  or  as  in 
Mimicry  she  becomes  conspicuous  enough,  but  is  in 
complete  superficial  resemblance  to  some  other  and 


FIG.  55.— The  larva  of  Puss  Moth 
in  its  terrifying  altitude  ;  from 
Trans.  Entom.  Soc. 


264          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

generally  very  different  creature.  The  purpose 
answered  is  the  same  in  all  the  cases,  viz.,  protection. 
In  the  one  case  the  leaf,  or  some  such  inanimate 
object,  is  passed  over  by  the  enemy,  and  so  the  dis- 
guise is  a  safe-guard  ;  in  the  other  the  living  insect 
that  is  resembled  is  unharmed,  and  of  necessity  the 
resembling  insect  must  share  in  its  immunity. 

That  in  greater  need  of  protection  we  find  the 
cause  of  the  difference  of  colour  of  the  female,  whether 
it  consist  in  decrease  or  increase  of  splendour  or 
elaboration  as  compared  with  the  male,  seems  corro- 
borated by  the  fact  that  where  protection  of  the  kind 
is  not  required,  in  other  words  where  protection  is  pro- 
cured independently  of  concealment — for  the  assump- 
tion of  mimetic  warning  colours  is  in  a  sense  conceal- 
ment— the  colouration  of  both  sexes  is  nearly  or  quite 
the  same.  In  the  specially  protected  and  mimicked 
groups  Heliconidae  and  Danaidse,  the  unpalatability  of 
which  seems  to  be  almost  universally  known  among 
insect  eaters,  no  sexual  difference  of  colour  is 
exhibited.  The  same  obtains  with  little  variation 
among  other  groups  of  insects  possessed  of  distasteful 
or  dangerous  qualities  advertised  by  Warning  Colours. 
For  example,  in  the  stinging  Hymenoptera,  as  well  as 
in  the  Cetoniidae  and  Buprestidae,  which  are  protect- 
ed by  their  .hardness,  the  two  sexes  may  be  said  to 
be  equally  well  coloured.  The  probable  combined 
influence  of  sexual  selection  in  determining  the  dis- 
similarity of  the  sexes  is  here  naturally  omitted. 

We  have  found  that  a  Lepidopterous  insect  mimics 
another,  such  only  as  we  have  every  reason  to  believe 
is  uneatable,  and  therefore  free  from  attack,  under 


vii  DEFENCES  OF  INSECTS  265 

cover  of  the  appearance  of  which  the  weak  and 
decaying  mimicking  form  shelters  itself.  As  might 
be  expected  from  their  usefulness,  corresponding 
imitations  exist  in  other  groups  of  insects.  They 
occur  particularly  among  the  Coleoptera,  but  these 
are  seldom  so  prominent,  so  easily  recognised,  or  so 
interesting,  nor  have  they  been  subjected  to  the  same 
full  investigation  as  the  beautiful  instances  in  Lepidop- 
tcra.  We  will  therefore  pass  on  to  consider  those 
cases  where  the  mimicry  occurs  between  species  so 
widely  separated  from  each  other  as  to  appertain  to 
distinct  orders. 

Sometimes  the  Lepidoptera  lose  the  external 
appearance  of  their  order.*  In  two  families  of 
British  day-flying  moths,  the  Sesiidse  and  ^Egeriidae, 
their  wing  scales  have  almost  disappeared  and  the 
wings  have  become  transparent,  while  the  body  is 
usually  straight  and  narrow,  and  the  colour  has  been 
modified  so  as  to  produce  a  more  or  less  complete 
resemblance  to  some  stinging  Hymenoptera.  One  of 
the  Bee  Hawk  moths,  Sesia  bombyliformis,  a  specific* 
name  recognising  the  similarity,  suggests  the  appear- 
ance of  the  male  of  the  common  Humble  Bee, 
B.  hortorum.  The  mimicry  of  the  Hornet  Clear- 
wing,  Sphecia  apiformis,  is  far  more  perfect,  and 
better  calculated  to  delude  the  enemy.  This  insect 
is  one  of  the  largest  of  these  moths,  and  is  a  striking 
imitation  of  a  hornet  or  good-sized  wasp.  The 
smaller  Currant  Clear-wing  (Trochilium  tipuliforme)^ 
known  for  the  depredations  of  its  caterpillars  on  the 
shoots  of  currant  bushes,  resembles  a  small  black 
wasp  abundant  in  gardens  at  the  same  season. 


266          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

Little  observation  has  been  made  on  the  living 
appearances  of  the  hundreds  of  species*  of  these 
groups  in  foreign  countries,  or  how  far  their  habits 
coincide  with  those  of  the  Hymenoptera  that  they 
specifically  resemble.  But  wherever  these  analogies 
occur,  their  meaning  may  be  inferred  to  be  the  same. 
When  we  see  a  moth  that  has  donned  the  livery 
of  a  bee  or  a  wasp,  we  seem  compelled  to  conclude 
that  the  assumption  is  intended  to  protect  the 
defenceless  form,  by  deceiving  insectivorous  animals, 
even  the  sharpest,  which  persecute  the  moth,  but 
which  regard  suspiciously,  or  deal  with  caution,  or 
at  once  avoid  the  hymenopterous  creature  whose 
sting  renders  it  troublesome  and  dangerous.  Certain 
species  of  the  clear-wing  group  have  opaque  wings, 
closely  resembling  those  of  species  of  Coleoptera 
inhabiting  the  same  district.  When  at  rest  the  wings 
are  closed  over  the  body,  like  the  elytra  of  beetles. 

No  order  is  so  frequently  mimicked  as  the 
Hymenoptera.  A  number  of  the  Diptera  or  two- 
winged  flies  resemble  bees  and  wasps,  and  doubtless 
derive  benefit  from  the  freedom  of  the  imitated  insects 
from  attack.  In  the  tropics  of  South  America 
certain  large  flies  mimic  stinging  Sphegidae  of  that 
country,  and  a  fly  of  the  genus  Asilus  corresponds  in 
the  colour,  both  of  its  wings  and  its  abdomen,  with 
the  handsome  bee  Euglossa  dimidiata,  the  mocker 
and  the  mocked  being  found  in  the  same  localities. 
A  striking  resemblance  exists  between  the  well- 
known  hornet  Vespa  orientalis  and  a  species  of  the 
dipterous  genus  Laphria.1  The  mimicked  hornet 
1  Proc.  Camb.  Phil.  Soc.  vol.  iii.  Feb.  1877. 


vii  DEFENCES  OF  INSECTS  267 

is  common  round  the  shores  of  the  Mediterranean, 
and  extends  through  Upper  Egypt,  Syria,  Arabia,  and 
eastwards  into  Hindoostan.  In  colour,  size,  shape, 
attitude,  and  mode  of  flight,  it  is  accurately  copied  by 
its  imitator.  At  home  the  Drone  Fly  (Eristalis\  a 
very  common  insect  belonging  to  the  Diptera,  is  mar- 
vellously like  the  male  of  the  ordinary  honey-bee  as 
regards  form  and  habits,  and  is  often  erroneously 
called  a  drone  from  this  circumstance. 

Many  of  the  Coleoptera  also  resemble  Hymenop- 
tera.  Charts  melipona,  a  South  American  beetle,  is  so 
named  from  its  resemblance  to  a  small  Melipona  bee. 
It  has  acquired  a  hairy  covering  on  the  thorax  and 
body  like  the  bee,  and  its  legs  are  tufted  in  a  fashion 
distinctly  opposed  to  that  usual  on  beetles.  Another 
Longicorn  Mr.  Bates  was  afraid  to  touch  lest  it  should 
sting,  it  being  exactly  like  a  small  common  wasp  of 
the  genus  Odynerus.  Some  Eastern  species  of  the 
Longicornes  adopt  the  garb  of  sawflies  (Tenthredin- 
idce},  and  there  are  many  instances  of  beetles  closely 
imitating  the  appearance  of  ants.  The  latter  are 
excessively  abundant  in  warm  climates,  and  apparently 
privileged  in  enjoying  general  freedom  from  attack. 
Turning  to  England,  a  common  beetle  (Clytus  arietis] 
resembles  a  wasp  in  a  striking  manner.  The  waisted 
body,  the  characteristic  black  and  yellow  bands,  and 
verily  the  mode  of  walking  of  the  wasp  have  been 
all  assumed  by  its  mimic. 

Bates  mentions  several  species  of  crickets  (Or- 
thoptera*}  of  South  America  which  resemble  different 
sand-wasps  of  large  size.  The  wasps  are  constantly 
on  the  out-look  for  crickets  with  which  to  provision 


268          ROMANCE  OF  THE  INSECT  WORLD       CHAP. 

their  nests,  so  that  it  is  to  the  interest  of  the 
mimickers  to  be  concealed  from  the  mimicked  forms 
themselves. 

Notwithstanding  the  immense  structural  difference 
between  the  Hemiptera*  and  Hymenoptera,  Mr.  Belt 
describes  a  Nicaraguan  bug  which  imitates  a  hornet, 
and  he  caught  the  mimic  in  his  net  fully  believing  it 
to  be  the  creature  feigned.  In  respect  of  the  dis- 
similarity of  appearance  of  the  orders  to  which  the 
insects  respectively  belong,  this  is  one  of  the  most 
extraordinary  instances  of  mimicry  on  record  (see 
Fig.  49). 

The  order  Coleoptera  likewise  serves  as  the  pattern 
for  many  feeble  members  of  other  groups.  In  the 
Philippine  Isles  a  pretty  cricket  (Condylodera)  is  com- 
pensated for  its  real  inoffensiveness  by  the  acquisition 
of  the  appearance  of  a  dreaded  active  and  predaceous 
tiger-beetle  (Tricondyla) ;  even  the  experienced 
naturalist  Mr.  Westwood  placed  it  among  the  tiger- 
beetles  in  his  cabinet,  and  it  was  long  before  he 
discovered  his  mistake.  Both  insects  occur  together 
on  trees,  but  while  the  mimicked  species  is  plentiful, 
the  mimicker  is  rare.  The  association  suggests  that 
the  disguise  not  only  shields  the  cricket  from  enemies 
who  dislike  or  fear  the  mimicked  forms,  but  saves  it 
from  the  attacks  of  the  beetle  itself.  In  the  Amazon 
valley  a  locust  mimics  a  tiger-beetle,  and  is  found 
in  the  same  situation.  Another  most  remarkable 
instance  of  these  resemblances,  is  that  of  a  grass- 
hopper in  the  Philippines  which  resembles  a  lady-bird, 
whose  convex  shape  is  totally  unlike  its  own  natural 
dress.  The  nauseousness  of  the  little  beetle  renders 


vii  DEFENCES  OF  INSECTS  269 

it  an  excellent  object  for  imitation.  Frequently  the 
peculiar  protection  of  the  mimicked  species  takes  the 
form  of  an  excessive  hardness,  such  as  insectivorous 
animals  fail  to  crush  or  to  eat.  It  is  easy  to  under- 
stand the  benefit  that  comparatively  soft-bodied  and 
eatable  insects  derive  from  fraudulent  reproduction  of 
this  indigestible  characteristic.  This  is  a  defence 
much  mimicked  by  other,  and  often  distantly  related, 
beetles. 

We  come  now  to  cases  in  which  the  affinity  of  the 
resembling   forms   is   more   distant   still,   where    the 
mimicker  is  distinguished  from    the  species   that   it 
mimics   by  the  wide  differences   that   separate   two 
classes  of  a  sub-section  of  the  animal  kingdom.     Both 
in  the  Old  and  the  New  World,  spiders  are  known  to 
resemble  ants.     The  deception  is  often  most  complete 
as  regards  form  and  colour,  and   the   habits  of  the 
imitator    carry    out    the    dissimulation.      One   such 
mimetic  spider  caught  by  Mr.  Belt  held  up  its  fore- 
legs to  represent  antennae,  and  they  were  used  in  the 
characteristic  manner.     In  Synageles  picata  and  Syne- 
mosyna  formica  (see  Fig.  51)  antennae  are  represented 
by  the  second  pair  of  legs.   The  walk  and  other  move- 
ments of  many  of  these  spiders  correspond  with  those 
of  their  models,  and  differ  strangely  from  the  motions  of 
their  own  allies.     Elizabeth  Peckham  in  describing  S. 
picata  (see  Fig.  50),  an  ant-like  spider  in  North  America, 
states  that  "  by  far  the  most  deceptive  thing  about  it  is 
the  way  in  which  it  moves.     It  does  not  jump  like  the 
other  Attidse,  nor  does  it  walk  in  a  straight  line,  but 
zig-zags  continually  from  side  to  side,  exactly  like  an 
ant  which  is  out  in  search  of  booty.  .  .  .  The   ant 


270          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

only  moves  in  this  way  when  it  is  hunting,  at  other 
times  it  goes  in  a  straight  line  ;  but  its  little  imitator 
zig-zags  always."  And  while  it  is  customary  for 
spiders  to  remain  nearly  motionless  when  they  are 
eating,  picata  "  acts  like  an  ant  which  is  engaged  in 
pulling  some  treasure-trove  into  pieces  convenient  for 
carrying.  I  have  noticed  a  female  picata  which,  after 
getting  possession  of  a  gnat,  kept  beating  it  with  her 
front  legs  as  she  ate,  pulling  it  about  in  different 
directions,  and  all  the  time  twitching  her  ant-like 
abdomen."  The  ants  mimicked  are  abundant,  and  as 
a  rule  are  exempt  from  persecution.  The  spiders  on 
the  contrary  are  particularly  relished  by  insectivorous 
birds,  so  that  there  seems  good  reason  for  inferring 
that  this  mimicry  is  protective. 

Lastly  we  arrive  at  the  most  extraordinary  cases  of 
Mimicry,  in  which  the  defenceless  species  assumes  the 
outward  dress  of  a  protected  form  belonging  to  a 
different  sub-kingdom.  Mr.  Bates  was  startled  by  the 
strong  resemblance  of  a  large  South  American  cater- 
pillar to  a  small  snake.  The  first  three  segments 
behind  the  head  were  dilatable  at  pleasure,  and  on 
either  side  it  had  a  great  black  pupillated  mark, 
imitating  an  eye.  That  a  poisonous  snake  was 
suggested  was  evident  by  the  appearance  of  keeled 
scales  on  the  crown,  produced  by  the  recumbent  feet, 
as  the  caterpillar  raised  the  anterior  end  of  its  body. 
Among  our  British  caterpillars,  that  of  the  Large 
Elephant  Hawk  Moth  (Chcerocampa  elpenor]  affords 
a  similar  example.  It  occurs  in  two  varieties,  a  green 
and  a  brown,  both  being  in  protective  keeping  with 
the  colour  of  their  food-plant.  On  each  side  of  the 


vii  DEFENCES  OF  INSECTS  271 

two  first  abdominal  segments  it  possesses  a  large  eye- 
like  spot,  not  in  any  way  specially  attractive  when  the 
insect  is  undisturbed,  though  the  marks  are  somewhat 
grotesque  (see  Fig.  52).  But  upon  the  approach  of  an 
enemy,  the  caterpillar  instantly  telescopes  its  head  and 
thoracic  rings  into  the  segments  that  bear  the  spots. 
These  segments  thus  become  swollen,  and  look  like  the 
head  of  the  animal,  upon  which  four  seeming  eyes  are 
very  noticeable  and  terrible  of  aspect.  The  incon- 
spicuous insect  is  at  once  changed  into  a  serpent-like 
form,  sufficiently  surprising  to  frighten  away  any  would- 
be  assailant  (see  Fig.  53).  Mr.  Poulton  states  that  it  is 
the  cobra  that  is  simulated  in  these  cases.  Like  other 
snakes  it  has  not  a  large  head,  and  its  eyes  are  small. 
It  inspires  fear  by  its  dilated  hood  with  its  great  eye- 
like  'spectacles,'  and  these  features  the  caterpillar 
copies  in  its  swollen  anterior  end  and  terrifying  spots. 
It  is  extremely  interesting,  Mr.  Poulton  remarks,  that 
the  caterpillar  should  imitate  a  feature  which  is  merely 
deceptive  in  the  snake  itself. 

The  assumption  at  will  of  a  like  mimetic  resemblance 
is  to  be  found  in  the  larva  of  the  Puss  Moth  (Cerura 
vimda,  see  Fig.  54).  When  at  rest  this  caterpillar 
harmonises  with  the  colour  of  its  surroundings,  and  is 
well  concealed.  But  as  soon  as  it  is  disturbed  it  with- 
draws its  head  into  the  first  body-segment,  dilating  the 
margin,  which  is  of  a  red  colour,  and  on  which  there  are 
two  black  spots,  like  two  eyes.  An  appearance  is  pro- 
duced of  a  huge  flat  vertebrate  face  (see  Fig.  55).  The 
caterpillar  also  turns  and  confronts  the  enemy.  Human 
beings  are  alarmed  by  the  attitude,  and  doubtless  it  is 
a  protection  against  the  most  audacious  vertebrate  foes 


272          ROMANCE  OF  THE  INSECT  WORLD      CHAP. 

of  the  mimic.  This  insect  is  possessed  of  other  means 
of  defence,  which  may  be  called  into  action  should  the 
terrifying  attitude  fail  to  repel  attack.  Elaborate  and 
numerous  defensive  appliances  probably  indicate  a 
much  and  long  persecuted  larva,  one  that  has  with- 
stood all  the  persecution  to  which  it  has  been  liable 
only  by  the  repeated  acquisition  of  new  means  of  re- 
sistance. There  is  experimental  proof  that  the  inter- 
pretation of  these  appearances  is  correct,  and  that  the 
assumption  of  these  mimetic  resemblances  is  of  real 
protective  value  by  inspiring  insect-eating  animals 
with  fear. 

In  a  relatively  few  cases  of  Mimicry  an  insect 
resembles  another  so  as  to  be  able  to  injure  it.  The 
latter  may  constitute  the  prey  of  the  mimic,  and  by 
virtue  of  its  deception  the  predacious  form  is  enabled 
to  approach  its  living  food  without  exciting  suspicion. 
Probably  the  close  resemblance  of  spiders  to  ants  may 
be  explained  in  this  way  in  a  few  instances.  Bates 
mentions  a  Mantis  in  the  Amazons  which  exactly 
resembles  the  white  ants  on  which  it  feeds. 

This  Mimicry  may  allow  the  aggressive  form 
to  lay  eggs  in  the  nest  of  that  mimicked,  at  whose 
expense  the  hatched  young  live,  either  upon  food 
stored  up  by  their  unhappy  hosts,  or  even  upon 
their  larvae.  Thus  the  larvae  of  two-winged  flies  of 
the  British  genus  Volucella  and  many  tropical 
Bombylii  are  parasitic  upon  the  larvae  of  particular 
species  of  industrious  bees.  Most  of  the  flies  are 
remarkably  like  the  bees  on  which  they  prey,  and 
enter  the  nests  unsuspected  to  deposit  their  eggs. 
Volucella  inanis  resembles  the  common  wasp  (  Vespa 


vii  DEFENCES  OF  INSECTS  273 

vulgaris),  but  its  disguise  is  less  perfect,  so  that  it 
dares  not  venture  within  the  portals  of  its  model.  It 
lays  its  eggs  at  dusk  at  the  entrance  to  the  abode, 
giving  the  larvae  a  chance  of  being  accidentally  carried 
in  by  the  wasps,  or  by  creeping  in  of  their  own 
accord.  As  it  is,  the  presumption  is  said  to  often 
cost  the  mother-fly  her  life,  owing  perhaps  to  the 
slight  failure  of  the  imitative  dress,  or  to  the  greater 
intelligence  of  the  wasp  as  compared  with  the  humble 
bee.  Hymenoptera  also  mimic  and  live  upon  the 
labours  of  home-building  species  of  their  own  order. 
Bees  of  the  genus  Nomada  resemble  Andrenidae,  and 
bees  of  the  genus  Psithyrus  are  almost  exactly  like 
the  humble-bees  (Bombi]  in  whose  nests  they  are 
reared.  On  the  banks  of  the  Amazon  Bates 
found  many  of  these  "  cuckoo  "  bees  and  flies,  which 
all  wore  the  livery  of  working-bees  peculiar  to  the 
country. 

There  are  cases  in  which  the  welfare  of  the  mimetic 
species  is  promoted  in  another  way.  The  insect  that 
resembles  another  does  not  injure  the  latter,  but  preys 
upon  an  animal  which  accompanies  it,  or  to  whom  the 
species  mimicked  is  indifferent.  In  the  opinion  of 
Professor  Meldola  certain  ant-like  spiders  from 
Africa,  described  by  Mr.  Mansel  Weale,  are  instances 
of  Aggressive  Mimicry  by  spiders  for  the  purpose  of 
preying  upon  flies,  which  are  often  found  in  company 
with  the  ants,  and  upon  which  the  latter  are  not 
predatory.  Both  the  ants  and  the  flies  are  said  to 
visit  the  same  trees  in  order  to  feed  upon  the  sweet 
secretions,  and  the  former  can  mingle  freely  with  the 
flies  without  causing  alarm.  The  spiders  by  mimick- 

T 


274          ROMANCE  OF  THE  INSECT  WORLD    CH.  vn 

ing  the  dress  of  the  ants  would   be  enabled  to  secure 
an  abundant  supply  of  food.1 

The  much  greater  frequency  of  Mimicry  with 
insects  than  with  other  animals,  and  the  perfection  of 
the  phenomenon  in  them,  are  probably  to  be  ascribed 
to  their  small  size  and  defenceless  condition  as  a 
whole.  These  characters,  combined  with  their  amazing 
fertility,  the  extent  to  which  they  are  preyed  upon  by 
the  larger  animals,  and  the  quickness  of  succession  of 
their  generations  are  reasons  why  the  operation  of 
natural  selection  produces  mimetic  and  other  pro- 
tective resemblances  more  numerous  and  more 
wonderful  than  in  any  section  of  the  animal  kingdom. 
Hence  the  abundance  and  striking  nature  of  imitation 
in  the  tropics,  where  insect  life  is  most  luxuriant, 
where  the  succession  of  the  generations  is  more  rapid, 
and  where  the  mutual  strife  between  the  attacked 
forms  and  their  attackers  is  considerably  keener  than 
in  temperate  and  cold  climates. 

1  Proc.  Entom.  Soc.  Lond.,  1878,  p.  xiv. 


GLOSSARY 

OF  THE  PRINCIPAL   SCIENTIFIC   TERMS   USED 
IN  THIS  VOLUME. 


Abdomen. — The  third  or  tail  region  of  the  body.  The  segments,  or 
rings,  of  which  it  is  made  up,  can  be  more  easily  distinguished 
than  those  of  the  other  regions.  In  adult  insects  (with  one 
exception)  it  is  destitute  of  locomotive  organs.  Many  larvae, 
however,  have  fleshy  sucker-feet,  or  prolegs,  attached  to  their 
abdomen.  These  are  shed  with  the  skin  when  the  larva  changes 
to  pupa. 

Abortion. — An  organ  is  said  to  be  aborted  when  it  has  been  arrested  in 
development  at  a  very  early  stage. 

Alveoli. — Applied  to  the  cells  of  bees. 

Amadou. — A  substance  prepared  from  a  fungus  (Folyporus  fomen- 
taritis],  found  upon  old  trees,  especially  the  oak,  ash,  fir,  cherry. 
Used  as  a  styptic  for  haemorrhage.  Boiled  in  a  solution  of  nitre 
it  is  employed  as  tinder. 

Amorphous. — Shapeless. 

Antenna — A  pair  of  jointed  appendages,  feelers,  or  horns,  placed  upon 
the  head  of  insects,  in  front  of  the  eyes  or  between  them,  and  not 
belonging  to  the  mouth.  Of  various  forms  and  length. 

Anterior. — Placed  before,  in  front. 

Apodous.  — Footless. 

Arachnida. — The  Spiders  and  their  allied  forms.  They  constitute  a 
well  defined  group  within  the  great  division  '  Articulata  '  of  the 
animal  kingdom.  Arachnids  are  divided  into  seven  orders,  of 
which  the  Araneklea  are  the  true  Spiders. 

Articulated. — Jointed.  The  Articulata  is  one  of  the  great  divisions  of 
the  Animal  Kingdom  characterised  generally  by  the  body  being 
divided  into  a  number  of  rings,  or  segments,  some  of  which  are 
possessed  of  jointed  limbs.  Insects  are  included  in  this  division. 

T  2 


276  GLOSSARY 

Atrophied. — Arrested  in  development  at  an  early  stage. 

Aurelia. — (Lat.).  Ancient  term  used  for  the  pupa,  or  third  stage  of 

insect  life. 

Bi-pinnate. — A  pinnate  leaf  has  leaflets  on  each  side  of  a  central  stalk 
or  mid-rib.  If  the  division  into  leaflets  is  similarly  repeated,  the 
leaf  is  bi-pinnate.  In  this  case  the  leaflets  which  are  attached  to 
the  common  stalk  are  termed  the  pinnae,  and  the  secondary  leaflets 
the  pinnules. 

Branchial. — Gills  or  organs  whereby  insects,  like  fishes,  breathe  the 
air  that  is  mechanically  mixed  with  water.  They  are  often  plate- 
like  expansions  of  the  body-wall,  and  are  largely  supplied  with  air- 
tubes,  or  tracheae,  which  are  separated  from  the  water  only  by  the 
thin  walls  of  the  organ.  Thus  the  air  contained  in  the  tracheae  is 
readily  purified  by  the  air  in  the  water. 

Capillary  Attraction. — If  a  capillary  tube  [that  is  a  tube  with  a  hole  so 
small  that  it  will  only  admit  a  hair  (capilla)]  of  glass  is  placed 
vertically  with  its  lower  end  in  water,  the  water  rises  in  the  tube 
to  a  higher  level  than  the  water  outside.  This  has  been  called 
Capillary  Action,  and  the  term  is  applied  to  many  other  phenomena 
which  depend  upon  properties  of  liquids  and  solids  similar  to 
those  which  cause  the  action  between  the  capillary  tube  and  the 
water. 

Cccropia. — A  genus  of  trees,  order  Moraceae.  C.  peltata  is  the  Trumpet 
tree  of  the  W.  Indies  and  S.  America.  Its  fibrous  bark  is  used  for 
cordage,  and  its  hollow  stem  and  branches  are  made  into  water- 
pipes  and  wind  instruments.  The  genus  is  named  from  Cecropia, 
the  original  name  of  Athens,  in  honour  of  Cecrops  its  founder, 
who  according  to  Athenian  tradition  was  first  king  of  Attica. 
Cecropia  was  subsequently  called  Athens  by  Athena  or  Minerva, 
who  obtained  the  right  of  giving  it  a  name  in  her  quarrel  with 
Neptune. 

Cellular. — See  Parenchyma. 

Chitine. — The  peculiar  chemical  substance  which  forms  most  of  the 
hard  parts  of  insects.  The  chitinous  coating,  or  covering,  is 
formed  from  underlying  skin-cells. 

Chrysalis. — A  term  applied  to  the  third  or  pupa  stage  of  insects, 
chiefly  that  of  butterflies  and  moths.  Suggested  by  the  bright 
metallic  spots  with  which  the  pupae  of  certain  butterflies  are 
adorned,  from  the  Greek  c/irusos,  gold.  Two  forms  of  this  word 
are  in  use,  chrysalis,  pi.  chrysalides,  and  chrysalid,  pi.  chrysalids. 

Coarctate. — Straitened,  contracted,  confined  in  a  narrow  compass, 
inclosed  in  a  case  or  covering,  so  as  to  give  no  indication  of  what 
is  within,  as  the  pupa  of  some  flies. 

Coccus. — The  genus  of  insects  includes  the  valuable  Cochineal.  In 
these  the  male  is  a  minute  active  winged  insect,  while  the  female 
does  not  acquire  wings,  and  in  fact  is  generally  a  motionless  scale - 
like  mass. 

Cocoon. — A  case,  usually  of  silken  material,  formed  around  the  body 
by  many  larvae,  as  those  of  moths,  wherein  they  change  to  the 
resting  or  pupa  stage  of  existence. 


GLOSSARY  277 

Coleoptera. — Or  Beetles,  a  vast  order  of  insects,  characterised,  as  the 
name  implies,  by  the  structure  of  the  first  pair  of  wings,  or  elytra 
as  they  are  called,  which  are  more  or  less  horny,  forming  sheaths 
for  the  protection  of  the  under  wings — the  true  organs  of  flight  in 
these  insects. 

Composite. — Plants  the  inflorescence  of  which  consists  of  very  numerous 
small  flowers  (florets)  arranged  upon  a  common  receptacle,  and 
crowded  into  a  dense  head  (capitulum}.  The  Daisy  is  a  common 
example. 

Concentric. — Having  one  common  centre. 

Congeries. — A  mass  of  small  bodies. 

Crop. — A  dilation  of  the  oesophagus  in  insects,  serving  as  a  reservoir  of 
food  See  gullet. 

Dimorphic. — Having  two  dissimilar  forms. 

Dimorphism. — The  condition  of  the  appearance  of  the  same  species 
under  two  conspicuously  distinct  forms. 

Diicdons. — The  term  is  applied  to  species  which  have  the  organs  of  the 
sexes  upon  different  individuals. 

Dipt  era. — Or  Flies — two- winged — comprise  insects  with  only  two 
wings,  minute  club-shaped  organs,  called  poisers  or  halteres,  taking 
the  place  of  the  hinder  pair 

Dorsal. — Of  or  belonging  to  the  back.  Relating  to  the  back,  or 
posterior  surface  of  the  body,  as  opposed  to  the  ventral  or  anterior 
surface. 

Elytra. — The  forewings  of  Beetles  and  Earwigs.  They  are  thick,  horny, 
or  leathery,  and  serve  as  cases  or  sheaths  for  the  membranous  hind 
pair  of  wings,  which  constitute  the  true  organs  of  flight. 

Embryo. — The  voung  insect  in  course  of  development  within  the  egg. 

Ephemera. — A  group  of  Neuropterous  Insects  allied  to  the  May  Fly. 

Epidermis. — The  superficial  layer  of  the  skin,  as  opposed  to  the  deep 
layer — the  true  skin. 

Epiphytal. — Many  tropical  species  of  Orchids  are  called  epiphytal — that 
is  growing  in  the  air,  attached  to  the  trunks  of  trees.  Their  aerial 
roots  do  not  reach  the  soil,  they  cling  to  the  bark,  and  ai'e  greenish 
or  white.  These  Orchids  derive  no  nutriment  from  the  tissues  of 
the  plant  on  which  they  grow,  but  absorb  moisture  from  the  air, 
and  from  what  trickles  down  the  tree,  containing  decaying  organic 
and  inorganic  matter. 

Excentric. — Removed  from  the  centre  or  axis. 

Exotic. — Foreign,  not  native,  the  opposite  to  indigenous  meaning 
native  to  a  country. 

Exuvia. — Cast-off  skin. 

Exuviation. — The  process  by  which  animals  shed  or  throw  off  their  old 
coverings,  skins,  &c.,  and  assume  new  ones. 

Eyes,  compound. — These  are  situated  one  on  each  side  of  the  head, 
and  are  of  considerable  size,  and  attain  a  marvellous  degree  of 
complexity.  Under  a  microscope  they  have  a  honey-comb  like 
appearance.  Each  of  the  little  six-sided  divisions  is  in  reality  a 
distinct  eye,  or  lens,  so  that  these  eyes  are  compound,  or  composed 
of  many  separate  small  eyes  or  ocelli  placed  side  by  side  ;  some- 


278  GLOSSARY 

limes  more  than  30,000  are  present.  In  true  larvae  these  eyes  are 
wanting. 

Eyes,  simple. — Usually  termed  ocelli.  Possessed  by  many  adult 
insects  in  addition  to  their  compound  eyes,  between  which  they 
are  situated,  on  the  crown  of  the  head.  Vary  in  number,  but  are 
usually  three.  Each  resembles  a  small  separate  eye  of  the  com- 
pound eye.  In  all  insects  that  undergo  a  true  metamorphosis, 
ocelli  are  the  only  organs  of  vision  in  the  larval  state.  In  that  con- 
dition there  may  be  several,  and  they  are  fixed  on  the  sides  of  the 
head. 

Fades. — Appearance,  aspect. 

Family. — A  group  of  genera  having  structural  features  in  common,  by 
which  they  resemble  one  another,  and  differ  from  all  other  genera. 
A  group  of  families,  similarly  associated,  constitutes  an  Order  ;  a 
group  of  species,  a  Genus. 

Feelers. — Or  palpi,  jointed  organs,  appended  to  the  lesser  jaws  and  in- 
ferior lip  of  the  mouth  in  insects. 

Fibro-vascular  bundles. — See  Parenchyma. 

Filament. — A  slender  thread-like  body. 

Formicites. — Ants  may  be  divided  into  three  groups,  characterised  by 
somewhat  important  structural  differences,  viz.,  Formicites, 
Ponerites,  and  Myrmicites. 

Fossorial. — Having  a  power  of  digging. 

Fuliginous. — Of  the  colour  of  dark  smoke. 

Fungus,  pi.  fungi. — A  class  of  cellular  plants.  Mushrooms  and 
Moulds  are  common  examples. 

Fuscous. — Of  a  dark  or  blackish  brown. 

Fusiform. — Shaped  like  a  spindle  ;  gradually  tapering  at  each  end. 

Gallic. — Denoting  the  acid  obtained  from  galls. 

Galls. — Excrescences,  chiefly  on  the  oak,  caused  principally  by  the 
puncture  and  deposited  eggs  of  the  family  Cynipidoe. 

Ganglion. — A  swelling  or  knot  on  nerves,  a  nerve  centre  containing 
nerve  cells,  and  receiving  and  giving  out  impressions. 

Genus. — A  group  formed  by  a  number  of  species  having  characters 
in  common. 

Glumes.  —The  scaly  bracts  of  grasses  and  sedges. 

Gullet,  or  oesophagus. — Extending  into  and  through  the  thorax,  is  the 
upper  or  narrowest  portion  of  the  alimentary  canal,  or  passage 
down  which  food  and  drink  pass  from  the  mouth  in  animals. 

Halteres,  balancers  or  poisers. — Appendages  in  two-winged  flies, believed 
to  represent  the  absent  hinder  wings.  See  Diptera.  In  the  males 
of  Coccidae,  which  also  possess  only  the  first  pair  of  wings,  the 
halteres  probably  aid  in  flight. 

Haustellate. — Furnished  with  a  sucker. 

Haustellum. — A  sucker.  The  term  is  applied  to  various  forms  of 
insect-mouths  adapted  for  suction. 

Head. — The  first  of  the  three  regions  into  which  the  body  is  divided. 
Like  the  other  regions,  it  is  believed  to  be  formed  of  several 
segments,  grown  or  fused  together  into  one  mass.  The  typical 
body-segment  possesses  a  single  pair  of  legs  only.  Certain  mouth- 


GLOSSARY  279 

parts,  and  other  portions  of  the  head,  are  supposed  to  be  modified 
legs,  and  to  represent  the  appendages  of  several  segments,  so 
that  it  follows  that  the  head  is  made  up  of  several  segments 
coalesced. 

Hemiptera. — An  order  or  sub-order  of  insects  which  includes  the 
various  species  of  Bugs.  They  agree  with  the  succeeding  order,  or 
sub-order,  Homoptera  in  the  peculiar  structure  of  the  mouth,  but 
differ  as  regards  their  wings.  In  Hemiptera  the  front  wings  are 
horny  or  leathery  in  the  basal  portion  and  membranous  at  the 
extremity,  where  they  overlap  each  other  when  at  rest ;  in 
Homoptera  they  are  membranous  throughout,  and  do  not  overlap. 
Sometimes  wings  are  wanting  irrboth  orders. 

Homoptera. — The  Cicadoe,  Frog-hoppers,  and  Aphides,  or  Scale  insects 
are  well-known  examples.  See  Hemiptera. 

Horns. — See  Antennae. 

Hymenoptera. — Membrane-winged  —  an  order  of  insects  possessing 
usually  four  membranous  wings  slightly  veined.  To  this  group 
belong  some  of  the  most  interesting  insects — gall-flies,  saw-flies,' 
ichneumons,  and  above  all,  ants,  bees  and  wasps. 

Ichneumonida. — A  great  family  of  Hymenopterous  insects,  the  females 
of  which  lay  their  eggs  in  the  bodies  or  eggs  of  other  insects. 

Imago. — The  perfectly  developed  and  reproductive  state  of  an  insect 
(usually  winged). 

Imbricate. — In  insects,  applied  to  scales  or  plates  which  overlap  each 
other  like  the  tiles  of  a  house. 

Insecta. — In  its  restricted  sense  this  term  is  applied  to  those  animals 
characterised  by  the  possession  of  only  six  legs — the  Hexapoda  or 
six-footed.  They  form  the  largest  class  of  that  great  division  of 
the  animal  kingdom  formerly  called  Articulata,  but  for  which 
the  term  Arthropoda  (joint-footed)  is  now  generally  adopted. 
Insect  comes  from  two  Latin  words,  ?'//,  into,  and  sccc,  to  cut,  and 
refers  to  the  fact  that  the  body  of  the  animals  thus  indicated 
appears  cut  or  divided  transversely  into  a  series  of  rings  or 
segments. 

Insectivorous.—  Feeding  upon  insects. 

[ungermanniece. — A  family  of  the  Hepaticce  or  Liverworts  in  which 
usually  a  slender  stem  bears  two-rowed  minute  leaves.  Nearly 
related  to  the  Musci  or  Mosses. 

Labiutn — The  under  lip,  the  second  transverse  plate,  which  bounds 
the  posterior  part  of  the  mouth.  Its  appendages  are  called  labial 
palpi. 

Labrum. — The  upper  lip,  constituting  the  anterior  boundary  of  the 
mouth. 

Lamina. — A  thin  plate  or  sheet-like  piece  ;  the  flatly  expanded  blade 
of  a  leaf — the  most  essential  part — is  so  called. 

Larva. — The  second  of  the  four  principal  stages  of  insect-life  ;  the  first 
condition  of  an  insect  at  its  emergence  from  the  egg.  During  this 
state  the  growth  of  the  insect  is  undergone. 

Lateral. — Appertaining  to  the  side  of  the  axis. 

Legs. — Insects  are  hexapodous,  or  provided  with  three  pairs  of  legs. 


280  GLOSSARY 

'  In  the  perfect  insect  each  leg  consists  of  four  chief  parts,  hip, 

thigh,  shank  and  foot,  or  scientifically,   coxa,  femur,   tibia  and 

tarsus.     Absent  in  the  majority  of  Hymenopterous  and  Dipterous 

larvoe.     False   legs    or    sucker-feet    are   universally    present    in 

Lepidopterous  larvae,  and  others. 

Lenticular. — Doubly  convex,  resembling  a  lens  ;  bean-shaped. 
Lcpidoptcra. — Scale-winged.     An  order  of  insects  characterised  by  the 

presence,  in  a  greater  or  less  degree,  of  minute  scales  on  the  wings. 

The  mouth  consists  chiefly  of  a  spiral  proboscis.     Two  groups, 

Butterflies  and  Moths,  together  form  this  order. 
lethargy. — Morbid  drowsiness,  unnatural  slumber. 
Lichens. — The  Lichen  Family,  a  distinct  class  of  cellular  cryptogamic, 

or  flowerless  plants.     A  lichen  usually  consists  of  a  well-developed 

layer    of    tissue  —  the    thallus  —  bearing     reproductive    bodies. 

Lichens  have  a  remarkable  relation  to  fungi  on  the  one  hand,  and 

to  algae  (the  sea-weed  family)  on  the  other. 
Ligneous. — Woody,  resembling  wood. 
Linear. — Like  a  line.     A  linear  leaf  is  one  that  is  not  only  many 

times  longer  than  it  is  broad,  but  is  of  nearly  the  same  width  from 

the  base  to  near  the  tip. 
Mandibles. — First  or  upper  pair  of  jaws,  opposed  horizontally  beneath 

the   upper    lip ;    vary   much   in   form ;    generally   strong   biting 

organs. 

Mandtbulate. — Provided  with  mandibles,  opposed  to  haustellate. 
Maxilla;. — Second  or  lower  pair  of  jaws  in  insects,  also  opposed  to 

each  other  horizontally  and  situated  below  the  mandibles,  compared 

with  which  they  are  much  more  complicated.     Furnished  with 

jointed  appendages  called  maxillary  palpi  or  feelers. 
Maxillary  Palpi. — See  Maxillae. 
Membrane. — A  thin  layer  or  skin  to  cover  or  wrap  up  some  part  of  an 

animal. 

Membranous. — Possessing  the  consistence  and  structure  of  a  membrane. 
Meso-thorax. — The  third  segment  of  the    body,   and    second  of   the 

thoracic  segments.     It  carries  the  first  pair  of  wings  and  second 

pair  of  legs. 

Metamorphoses.  — Or  transformations,  changes  with  regard  to  form. 
Mela-thorax. — The  fourth  segment  of  the  body  of  an  insect,  and  third 

or  hinder-most  of  the  three  rings  forming  the  true  thorax.     It  bears 

the  second  pair  of  wings  and  third  pair  of  legs. 
Mimetic. — Applied  to  animals  or  organs  which  resemble  each  other  in 

appearance,  but  not    in  essential   structure ;    appearing    like    an 

imitation. 
Mishna. — Or  text,  the  codification  of  the  traditionary  and  unwritten 

laws  of  the  Jews,  believed  to  have  been  commenced  in  the  second 

or  third  century  after  Christ.     A  two-fold  commentary  by  learned 

Rabbins  was  subsequently  appended  to  it. 
Moulting. — The  shedding,  or   stripping  of   the    skin,   or   coverings, 

undergone  by  insects  during  their  development. 
Mouth-parts. — The  typical  form  exists  in  the  biting  insects,  and  consists 

of  six  pieces,  an  upper  lip  or  labrum,  an  under  lip  or  labium,  with 


GLOSSARY  281 

two  pairs  of  jaws  acting  horizontally  between  them,  the  mandibles 
and  maxilloe.  The  maxilla;  and  labium  are  each  furnished  with  a 
pair  of  feelers,  known  respectively  as  the  maxillary  and  labial 
palpi.  No  organs  in  the  body  vary  more  than  the  mouth-parts, 
but  they  have  been  divided  into  two  great  groups,  the  biting  and 
the  sucking.  Among  these  many  minor  differences  occur.  Thus 
of  the  biting  insects,  some  require  jaws  suited  for  seizing  and 
tearing  prey  ;  others  are  vegetable  feeders,  and.  their  jaws  are 
adapted  for  chewing.  Of  the  sucking  insects,  some  have  merely 
a  sucking  tube,  to  sip  up  the  nectar  from  flowers  ;  others  art  in- 
strument to  pierce  the  coverings  of  animals,  before  they  can  obtain 
the  living  fluid. 

Natural  Selection,  or  the  Survival  of  the  Fittest. — The  natural  preser- 
vation of  such  differences  and  variations  as  arise,  and  are  beneficial, 
to  the  individual,  and  the  destruction  of  those  which  are  injurious, 
under  its  conditions  of  life.  By  this  principle,  the  individuals 
which  in  any  way,  even  the  slightest,  have  the  advantage  over 
others — which  are  strongest,  swiftest,  most  protected,  &c. — have 
the  best  chance  of  surviving,  and  of  propagating  their  kind. 

Neuration. — Or  venation,  the  arrangement  of  the  so-called  "  veins  "or 
"  nerves  "  in  the  wings  of  insects. 

Neuters. — See  Workers. 

Ntitrition. — That  process,  peculiar  to  living  bodies,  by  which  food  is 
finally  converted  into  the  substance  of  tissues  and  organs,  thus 
repairing  waste  and  admitting  of  growth. 

Nyinpli. — Old  name  for  pupa.  Now  generally  used  to  designate  the 
latter  portion  of  the  life  of  an  insect  with  an  incomplete  metamor- 
phosis, previous  to  its  change  to  the  winged  and  mature  state  ;  an 
active  pupa. 

Oblique.  — Not  perpendicular,  not  parallel,  deviating  from  the  straight 
line. 

Ocelli.—  See  eyes! 

(Esophagus. — See  gullet. 

Order. — An  assemblage  of  families  having  structural  features  in 
common. 

Organism. — An  organised  being,  be  it  plant  or  animal. 

Orthoptera.  —  Straight-winged.  Grasshoppers,  locusts,  crickets, 
walking-stick  insects,  cockroaches,  &c.  The  larvae  when  they 
quit  the  egg  differ  principally  from  the  mature  insects  merely  in 
the  absence  of  wings.  They  are  active  throughout  life. 

Oval — Egg-shaped,  oblong. 

Ovipositor. — Generally  the  most  conspicuous  appendage  of  the  abdomen 
is  the  ovipositor  of  the  female,  an  instrument  whereby  she  lays  her 
eggs.  Its  form  is  various,  and  sometimes  it  is  of  great  length.  In 
the  Hymenoptera  (which  see)  it  is  frequently  modified  into  a 
sting. 

Palpi. — Jointed  appendages,  or  feelers,  placed  on  the  lower  jaws 
(maxilla)  and  lower  lip  (labium)  of  the  mouth  in  insects. 

Papilionaceous. — The  Papilionacece  is  a  sub-order  of  plants  belonging 
to  the  large  and  important  natural  order  Leguminosre.  From  a 


282  GLOSSARY 

fancied  resemblance  to  a  butterfly,  the  irregular  flowers  have  been 
called  papilionaceous,  or  butterfly-like.  The  flower  of  the  garden 
pea  may  be  taken  as  the  type. 

Parasite. — (From  a  Greek  word,  meaning  one  who  eats  at  the  expense 
of  another  at  table).  An  animal  living  in  or  upon,  and  at  the 
expense  of  another.  Parasitic,  growing  in  or  upon,  and  deriving 
support  from  another. 

Parenchyinatous. — The  parenchyma  of  a  leaf  is  the  cellular  tissue 
surrounding  the  vessels  or  veins,  and  inclosed  within  the  covering 
or  epidermis.  It  contains  the  green  colouring  matter.  It  is  a 
tissue  composed  of  short  cells,  their  diameter  being  nearly  equal  in 
every  direction.  1}\z.  fibro-vascular  bundles  constitute  the  veins. 

Pedal. — Appertaining  to  a  foot. 

Pedicle. — A  small  short  foot-stalk,  a  little  stem. 

Persistent. — Constant,  not  falling  off. 

Petiolated.  —  Stalked,  supported  on  a  stem. 

Petiole — Or  leaf-stalk,  the  stalk  supporting  the  blade  or  lamina  of  a  leaf, 
and  connecting  the  blade  and  the  stem. 

Pigment. — The  colouring  matter  contained  in  cells  produced  generally 
in  the  superficial  parts  of  animals. 

Pinnule. — See  bi-pinnate. 

Poisei's. — See  Halteres. 

Pollen. — Usually  minute  grains  or  dust  produced  within  the  anthers  of 
flowers,  and  conveyed  to  the  stigma,  by  means  of  which  the 
fecundation  of  the  seeds  is  effected.  This  fertilisation  is  brought 
about  by  one  or  more  tubes  (pollen  tubes)  which  are  put  forth  by 
the  pollen-grains  adhering  to  the  stigma,  and  penetrate  through  the 
tissues  until  they  reach  the  cavity  of  the  ovary.  Here  they  come 
into  contact  with  the  ovules,  the  bodies  that  eventually  develop 
into  the  seeds. 

Pollinintii)  pi.  pollinia. — In  most  plants  the  pollen  consists  of  minute 
grains,  entirely  distinct  from  one  another.  In  some,  however,  as 
in  the  Orchids,  the  grains  are  firmly  united  together  by  a  sticky 
substance  into  pollen  masses,  or  pollinia,  within  the  anther  lobes. 

Posttrior. — Placed  after,  hinder. 

Proboscis. — In  butterflies  and  moths,  the  sucking  tube  or  trunk  formed 
by  the  modification  of  the  lower  jaws  or  maxillae. 

Process. — A  projection,  prominence,  protuberance. 

Prolegs. — Fleshy  organs  or  sucker-feet,  enabling  caterpillars  to  grasp 
firmly  stems  and  other  surfaces,  and  assisting  them  in  their  move- 
ments. These  false  or  abdominal  legs  are  universally  present  in 
Lepidopterous  larvre,  in  some  Hymenoptera,  &c.  Their  structure 
is  often  exceedingly  curious,  as  in  the  caterpillar  of  the  Goat  Moth. 

Pro-thorax. — The  first  of  the  three  segments  forming  the  intermediate 
region  of  the  body  known  as  the  thorax.  Its  appendages  are  the 
anterior  pair  of  legs. 

Pupa. — The  third  of  the  four  chief  stages  in  the  development  of  an 
insect.  Often  quiescent,  but  sometimes  active.  In  this  state  the 
wings  of  the  adult  exist  in  a  rudimentary  condition,  and  from  it 
the  insect  emerges  in  the  perfect  (winged)  reproductive  form.  The 


GLOSSARY  283 

pupa  state  of  butterflies  is  often  called  the  chrysalis,  that  of  insects 
with  an  incomplete  metamorphosis,  as  the  grasshopper,  is  frequently 
designated  nymph. 

Qucrcus. — A  highly  important  genus  of  trees,  order  Cupuliferse.  There 
are  two  varieties  of  British  oaks,  Quercus  scssiliflora  {Robur}  and 
pedunculata.  Q.  infectoria,  from  Asia  Minor  and  Turkey,  is 
valuable  for  its  wood,  and  especially  for  its  galls,  from  which 
tannin  and  gallic  acid  are  derived,  used  in  ink-making  and  for 
photographic  purposes.  Nearly  all  the  cork  of  commerce  comes 
from  a  species  of  the  oak  (Q.  suber)  growing  in  Spain,  southern 
France  and  Italy,  and  northern  Africa. 

Radicle.  — The  rudiment  of  the  root  of  an  embryo  plant. 

Ramification. — Division  or  separation  into  branches;  the  issuing  or 
spreading  of  small  vessels  from  a  large  one. 

Raptorial. — Adapted  for  seizing  prey. 

Regiirgitation. — The  act  of  pouring  or  swallowing  back  by  the  same 
orifice  or  place  of  entrance. 

Respiration. — The  act  of  breathing.  The  process  by  which  the  blood 
continually  absorbs  the  gas  known  as  oxygen  from  the  air,  and 
gives  off  in  exchange  carbonic  acid,  thus  effecting  its  purification. 

Respiratory. — Pertaining  to,  or  serving  for  respiration. 

Reticulated. — Marked  like  network. 

Rudimentary. — In  an  imperfectly  developed  condition. 

Rufescent. — Somewhat  reddish. 

Rufous. — Reddish,  of  a  red-brown  colour. 

Sac. — A  bag  or  pouch. 

Saliva. — The  fluid  or  chief  secretion  of  the  mouth  ;  derived  from  various 
glands. 

Salivary. — Secreting  or  conveying  saliva.  The  salivary  glands  of 
insects  are  appendages  to  the  alimentary  canal,  and  open  near  the 
mouth.  They  vary  in  form  and  number,  and  sometimes  are  not 
present.  In  Lepidopterous  larvae  they  constitute  the  silk  glands, 
and  have  a  distinct  opening  through  the  spinneret  (which  see). 

Segments. — The  transverse  rings  of  which  the  body  of  an  insect,  and  of 
certain  other  animals,  is  composed.  Their  ring-like  nature  is  best 
seen  in  larvae,  and  in  the  tail  portion  of  adult  insects.  In  the  latter 
the  rings  are  grouped  into  three  sets  or  regions,  forming  the  head,  the 
thorax  and  abdomen.  In  the  larva  state  this  grouping  is  not  distinct. 

Skeleton. — The  skeleton  of  an  insect  is  formed  of  the  hardened  body- 
wall  or  skin,  which  furnishes  support  to  the  softer  organs.  This 
hardening  is  due  to  the  deposition  in  it  of  a  horny  substance 
termed  chitine. 

Species.—  An  assemblage  of  individuals  having  structural  features  in 
common. 

Specific. — That  designates  the  species,  or  constitutes  it. 

Spheroidal. — Having  the  form  of  a  spheroid,  i.e.,  a  body  approaching 
to  the  form  of  a  sphere,  or  the  round. 

Spinneret. — A  projecting  papilla  situated  within  the  mouth  of  many 
caterpillars,  communicating  internally  with  glands  which  secrete 
silky  material,  externally  with  the  outside.  Through  this  organ 


284  GLOSSARY 

the  material,  in  the  form  of  a  viscous  fluid,  is  forced  in  two  very 
delicate  streams,  which  unite,  and  on  exposure  to  the  air  harden 
into  a  single  continuous  thread  of  silk. 

Spiracles. — The  breathing-pores  or  apertures  whereby  the  internal 
respiratory  system,  or  breathing  tubes  (tracheae)  of  insects,  com- 
municate with  the  air.  Usually  'situated  along  the  sides  of  the 
body,  and  do  not  occur  on  the  head.  Their  number  varies,  but 
there  is  never  more  than  one  pair  on  a  single  segment  of  the  body. 
A  common  form  of  structure  consists  of  a  horny  oval  ring,  within 
which  is  a  valve,  made  up  of  converging  fibres,  guarding  the  ex- 
ternal entrance.  At  a  short  distance  within  this  valve  a  second  may 
be  found,  of  more  complicated  form. 

Spiral. — Winding  like  a  screw. 
Succulent. — Juicy,  moist. 

Sucker-feet.  —  See  Prolegs. 

Suctorial. — Adapted  for  sucking. 

Tarsus. — (pi.  tarsi)  The  fourth  chief  division  of  the  leg  in  insects, 
that  which  is  popularly  called  the  foot.  It  is  made  up  of  segments, 
but  is  liable  to  numerous  modifications.  The  distal  segment  bears 
one  or  more  claws,  which  are  sometimes  strongly  toothed,  so  that 
there  may  appear  to  be  four,  or  even  six,  claws. 

7^awny, — A  pale  yellow. 

Tegument.^Cover,  skin. 

'Thoracic. — Of,  or  relating  to,  the  thorax. 

Thorax. — The  second  or  intermediate  region  of  the  body.  Formed  of 
three  segments,  known  respectively  as  the'pro-thorax,  meso-thorax 
and  meta-thorax.  Readily  recognised  for  its  appendages,  viz. , 
three  pairs  of  legs,  and  never  more  than  two  pairs  of  wings.  Each 
segment  bears  one  pair  of  legs,  and  in  winged  insects,  the  wings 
are  carried  by  the  two  hinder  segments. 

Tibia. — The  third  chief  part  or  shank  of  the  leg  in  the  perfect  insect, 
coming  between  the  thigh  (femur)  and  the  foot  (tarsus).  In  insects 
that  burrow  in  the  ground,  this  portion  is  much  broadened,  and 
shaped  somewhat  like  a  hand. 

Tissue. — The  elementary  or  essential  structures  of  which  organs  are 
composed. 

Trachea. — Breathing-tubes  of  insects  communicating  with  the  outside 
by  small  mouths,  or  pores  (spiracles).  By  means  of  branching, 
these  tubes  carry  the  air  through  every  portion  of  the  insect,  so 
that  the  various  tissues  are  supplied  with  oxygen  without  the  inter- 
vention of  blood,  as  in  the  higher  animals.  The  walls  of  these  air- 
tubes,  like  the  body-wall,  are  made  up  of  three  layers,  and  the 
outer  layer  of  the  wall  of  the  body  corresponds  with  the  inner 
layer  of  the  wall  of  the  tube.  The  latter  is  shed,  with  the  outer 
skin  of  the  body,  when  the  larva  moults.  In  many  adults  with 
powerful  flight,  the  tracheae  are  dilated  into  numbers  of  minute  sacs. 

Trimorphic. — A  species  is  so  designated  which  presents  three  distinct 
forms. 

Tubercle. — A  small  protuberance. 

Ttiberculated. — Possessed  of  tubercle-like  prominences. 


GLOSSARY  285 

Type. — The  perfect  representation  of  anything.  Typical,  applied  to  an 
individual  which  possesses  in  a  marked  degree  the  characteristics  of 
the  species,  or  to  a  species  similarly  exhibiting  the  essential  features 
of  the  order. 

Unctuous. — Fat,  clammy. 

Valve. — Folds  of  membrane  which  guard  certain  orifices  and  channels, 
allowing  any  fluid  to  pass  in  one  direction,  but  offering  a  barrier 
to  its  backward  movement. 

Venation,  or  Neuration  in  Insects. — The  arrangement  of  the  so-called 
"veins  "  or  "  nerves  "  of  the  wings.  A  wing  is  first  developed  as 
a  tiny  sac-like  projection  from  the  side  of  the  body.  As  formation 
goes  on,  the  two  walls  of  this  sac  become  united  throughout  their 
greater  part,  and  various  thickened  lines  are  usually  apparent, 
which  constitute  the  framework  of  the  wings,  and  are  termed  the 
veins  or  nerves.  Within  the  latter  a  canal  or  tube  often  exists 
for  the  circulatory  fluids,  and  they  are  likewise  traversed  by  the 
air-tubes,  or  tracheae.  Venation,  in  botany,  the  arrangement  of 
the  ribs  and  veins,  or  framework,  in  the  blades  of  leaves. 

Ventral. — Pertaining  to  the  abdomen  or  anterior  surface  of  the  body  ; 
the  opposite  of  dorsal. 

Vermiform.  — Worm-like. 

Vertebrate  Animals  or  Vertebrata.  — The  highest  division  of  the  animal 
kingdom,  characterised  by  the  possession  in  most  cases  of  a  back- 
bone or  vertebral  column  composed  of  numerous  joints  or  vertebra, 
which  constitutes  the  centre  of  the  hard  internal  bony  framework 
or  skeleton  of  the  body,  and  protects  the  central  parts  of  the 
nervous  system. 

Vilmrnum. — (L.  the  way-faring  tree).  A  genus  of  elegant  flowering 
shrubs,  belonging  to  the  natural  order  Caprifoliaceae — the  Honey- 
suckle family.  V.  opulus  is  the  common  Guelclres  Rose  or  Snow- 
ball tree,  the  flowers  of  which  appear  in  June.  So  named  from  a 
district  in  the  Low  Countries,  called  Gueldres-land,  where  it  is 
extremely  abundant.  V.  lantana  is  the  Mealy  Gueldres  Rose, 
sometimes  called  Cotton  Tree  from  its  general  mealiness. 

Viscous. — Glutinous,  sticky,  like  bird-lime.  (L.  viscum,  the  mistletoe, 
a  word  also  applied  to  bird-lime  made  from  the  berries  of  the 
mistletoe). 

Weevils. — A  family  belonging  to  the  great  order  of  beetles  (Coleoptera). 
They  may  generally  be  known  by  a  snout  or  proboscis  on  the 
head. 

Wings. — Insects  have  normally  two  pairs  of  wings  ;  the  Diptera  and 
others,  however,  have  only  one  pair,  while  many  are  entirely 
destitute  of  these  appendages.  When  a  single  pair  only  is 
present,  it  is  almost  invariably  the  first  pair,  and  in  Diptera,  &c., 
the  hinder  pair  is  represented  by  minute  organs,  called  halteres, 
balancers,  or  poisers.  Wings  vary  much  in  texture,  form,  nature 
of  surfaces,  and  venation.  As  regards  the  first-mentioned  character, 
the  greatest  variations  are  exhibited  by  the  first  pair,  and  special 
names  have  been  applied  to  those  wings  presenting  the  variations 
in  a  marked  degree  ;  among  these  are  the  elytra.  Development 


286  GLOSSARY 

of  wings  commences  in  the  early  period  of  larva.  After  last  larval 
skin  is  assumed,  previous  to  change  to  pupa,  rudiments  of  wings 
beign  to  form,  of  the  size  of  pins'  heads,  beneath  external  covering 
of  hinder  parts  of  thorax.  They  continue  to  grow,  and  just  before 
this  last  larval  skin  is  cast,  their  existence  is  distinctly  indicated  by 
the  swollen  appearance  of  the  segments.  Are  much  enlarged  when 
insect  turns  to  pupa,  and  when  subsequently  pupa  skin  is  burst,  the 
soft  thick  organs  dry,  and  acquire  full  expansion.  Their  gradual 
formation  can  be  well  seen  in  insects  with  an  incomplete 
metamorphosis. 

Workers. — Females  of  certain  social  insects,  such  as  the  ant  and  bee, 
the  sexual  organs  of  which  are  imperfectly  developed.  Their 
function  is  to  perform  all  the  laborious  offices  for  the  community. 
Formerly  they  were  believed  to  be  devoid  of  sex,  and  were  thus 
termed  neuters.  Experiments  have  proved  that  the  cause  of 
this  differentiation  of  sex  depends  upon  the  nature  of  the  food  with 
which  during  the  larval  state  the  bee  is  fed.  In  all  probability, 
this  explanation  applies  also  to  ants. 


INDEX 


INDEX 


ABDOMEN,  the  seat  of  certain  systems,  18 
Acacia  attacked  by  beetle-grubs,  99 
Acraeidae,  as  models  for  mimicry,  255,  260 
Adaptation,  high,  of  lepidoptera  to  floral 

diet,  62 
of  external  colouring  to  conditions  of 

life,  204 
Adaptive  colouring,   principle   of,  solved 

by  theory  of  natural  selection,  205 
to    what    formerly    attributed  ;     in- 
adequacy of  such  solutions,  205 
Adjustment  of  colour  is  adaptive,  241 

is  produced  and  maintained  by  natural 

selection,  241 

Adult  insects  subject  to  parasites,  40 
./Egeriidae,  mimicry  of,  265 
Aggressive  mimicry,  272 
Aggressive  resemblance,  223,  224,  226 
Agricultural  Ant,  of  American  plains,  57, 

I35,  140 

of  Florida,  57,  135,  140 
of  Texas,  where  found,  135  ;  disks  and 
paths,     underground     store-rooms, 
135  ;  marvellous  work  of  clearance 
of  disks   and   avenues,    use   of,    56, 
136 ;     refuse     heaps,     137  ;     stored 
grain,  use,  137  ;  question  of  cultiva- 
tion of  grain  by,  138  ;  mound  disks, 
internal  structure,  138,  139 
Alimentary  canal  in  insects,  21 
Alluring  colouring  of  mantises,  223,  226 
Analogy  between   economy  of  honey-ant 
and  that  of  bee  in  storage  of  food,  51 
Andrenidae,  homes  of,  74 

as  models  for  mimicry,  273 
Animal-feeding  insects,  37 
Animal  matters  a  food  of  insects,  41 
Ant-cows,  42,  45,  150 

their  protection  by  ants,  43,  150 
domestication  of,  43 
food  of,  44,  150 
breeders  of,  44 
Ant-honey,  uses  for,  54 
Ant-lion,  stratagem  of,  66 
Antennae  as  appendages  of  head,  19 


Ants, 

European,  providence  of,  55,  57 

attending  aphides,  42 

remarkable  instance  of  foresight  of,  44 

nursing  duties  of,  48,  124 

slave-making,  49 

storage  of  food  by,  51,  55,  57,  146 

nests,  three  types  of,  120 

workers  in  earth,  120 

eggs,  so  called,  125 

as  guardians  of  plants,  149 

and  beetles,  45 

and  Cocci,  45,  150 

carpenter,  146 

wood,  120 

mason,  119,  128 

as  models  for  mimicry,  267,  269,  272,273 

saiiba,  133 
Apis,  indica.  and  nigrocincta,  162 

dorsata,  162 
JJoralis,  163 

in  West  Indies  and  South  America, 

163 
Apoica,  architecture  of,  184 

canopy  of  nest,  use  of,  185 

occasional  hexagonal  shape  of  nest,  186 
Apparent     suddenness    of     metamorphic 

changes,  31 

Appendages  of  head,  19 
Aquatic  larvae,  12,  13,  105 

caddis  flies,  12,  105 

of  hydrocampidae,  107 
Architecture,  ins3ct,  propriety  of  use   of 

word,  119 

Argyronetra  aquatica,  home,  construc- 
tion of,  115 

in  England,  115 

breather  of  atmospheric  air,  115 

deposition  of  eggs  of,    116 

life  of  young,  116 

Association,  of  bright  colour  with  distaste- 
ful qualities,  246 ;  part  played  by 
natural  selection  in,  247,  248 

of  wings  with  function  of  respiration, 

18 

Attachment  of  wings,  17 
Azara,  on  Chiguana,  198 

u 


290 


INDEX 


i; 


BALANCE     of    life    between     vegetables, 

insect-pests,  and  parasites,  41 
Bark  and  lichen,  resemblance  to,  209,  213, 

214,   2l8,   222 

Bates,  on  sauba  ant,  134 

on    similarity   between     unpalatable 

butterflies,  251 
on  theory  of  mimicry,  254 
theory  of  mimicry   of,   confirmed  by 
Wallace's     interpretation      of     the 
liability  of  the  female  to  assume  this 
method  of  defence,  262  ;    claim  for 
natural  selection  to  have  produced 
mimicry  also  favoured  by  Wallace's 
interpretation,  262 
on  insects  which  mimic  vertebrates, 

270  ^ 

Beauty  of  insect  architecture,  118 
Bee,  larvae,  apodous,  16 
crop  in,  22 
hive,  73,  156 

Bee  hawk  moths,  mimicry  of,  265 
Bees,  leaf-cutting,  82 

mason,  solitary,  79  ;  social,  164 

carpenter,  75 

parasitic,  49,  273 

mining,  74 

and  ants,  length  of  pupal  period  of,  1 1 

solitary,  73 

as  models  for  mimicry,  265,  266,  267, 

272,  273 
nursing,  48 

British  wild,  74,  79,  82,  154 
Beetles,  bees,  successive  changes  of,  2,  3 

mimetic  analogies  among,  265 
Belt,  on  mimicry  of  ants  by  spiders,  269 

on  mimicry  of  hornet  by  bug,  268 
Birds  and  hairy  larvae,  245 
Birth  of  insects,  retarded,  3   t 
Body    of   insects,     divisible     into     three 

regions,  15 

regions  of,  how  formed,  15 
Bombardier  beetles,  244 
Bombi,  as  models  for  mimicry,  265 

as  models  for  aggressive  mimicry,  273 
Boinbus  lapidarius,  161 
ntitscorum,  156 

terrestris,  most  prolific  of  Bombi,  161 
Bot  flies,  parasitism  of,  37 
Branchiae,  27 
Breathing  energy  of  grub  and  adult  insect 

compared,  26 
Bright  colour  as  a  warning,  247 

its  value,  247,  248 

Brilliancy  may  enhance  concealment,  206 
British,  and  European  moths,  special  pro- 
tection of,  218 
Autumn  and  winter  moths,  protective 

tints  of,  219 

lepidoptera,  protective  mimicry  in,  260 

wild  bees,  154  ;  popular  names  of,  154  ; 

eighteen  or  twenty  species   in  this 

country,  155;  comparison  of  habita- 


tions with  hive,  156,   162;  deep  bur- 
rowers,  compared  with  carder,  162  ; 
compared  with  hive,  162 
tree  wasps,  175 
V.  Britannica,  globe-like  dwelling  of, 

!75 
caterpillars  which  mimic  vertebrates, 

270 

Broad   expanse  of  wing  of  showy  butter- 
flies, one  explanation  of,  253 
Bug,  mimicry  of,  268 
Bull's  horn,  standing  army  of,  149 
Butterflies,  successive  changes  of,  2 
preparation  for  change  to  pupa,  9 
and  flies,  crop  in,  22 
wings  of,  easily  seized  by  enemy,  253 
that  are  objects  of  mimicry,  254 ;  proof 
that   they  are    specially  protected, 
255  ;  on   other  hand  that  mimickers 
need  protection,  256 
protective  resemblance  of,  209,  215 
mimicry  in,  258 


CADDIS,  acquisition  of  locomotion  of,at  end 
of  pupa,  12 

homes  of,  105 
Calandra,  larvae  of,  99 
Capincha,  dung  of,  forms  nest  of  Myrape- 

tra,  197 

Carabidae,  nauseousness  of,  while  not  con- 
spicuous, 248 
Card-board  makers,  186 

enormous  size  of  nests,  187 
Carder  Bee,  description  of  nest,  156 

dispersion  of  company,  160 

formation  of  society  in  spring,  160 
Career   of  insects  after  entering    perfect 

stage,  13 
Carpenter  ants,  120,  146 

F.  fuliginosa.)  residences  in  trees,  146 

in  roots,  147 

wood  carved  by  becomes  black,  147 
Carpenter  bees,  75 
Caterpillars,  with  a  liking  for  wax,  42 

destructive  to  vine,  101 

social,  societies  of,  119 

gregarious  habits  of,  a  "warning,"  248 

variable  protective  resemblance  in,  238 

unpleasant    properties    possessed    by, 
244,  245,  246 

mimicking  snakes,  270 
Cecropia,  150 
Chcerocampa  elpenor,  mimicry  of  larva  of, 

270 

Chalicodoma,  79 
Changes  of  colour  corresponding  to  changes 

of  environment,  226 
Chartergus  apicalis,  nest,  grace  of,  189 

interior  of  nest,  189 

spindle,  189 

axes,  189 

accessory  props,  190 

mode  of  enlargement,  191 

fragility  of,  191 


INDEX 


291 


Chartergns  ckartariits,  nest,  187 
card-board  of,  187 
Reaumur  on,  188 

shape  and  size  of  nest,  mode  of  attach- 
ment, 188 
interior,  188 

mode  of  enlargement,  189 
Chelostomes,  81 
Cherry  galls,  92 
Chiguana,  or  Lecheguana  wasp,  198 

Azara  on,  198 
Chitine,  20 
Choice  of  vegetable  food  for  insects,  almost 

limitless,  34 

Chrysalides,    variable     protective    resem- 
blance in,  232 

supposed    photographic    sensitiveness 
„,         °(.  233 

Chrysalis,  term  for  pupa  stage,  10 
Chrysididae,  246 
Cicindela,  colour  of,  an  exact  reproduction 

of  colour  of  surroundings,  208 
C.  campestris,  habits  of  larvae,  100 
Clothes  moth,  103 
Coarctate  state  of  flies,  9,  ir 
Cocoons,  as  shelters  for  pupae,  9 
Cold,  damp,  effects  on  larvas,  8 
Coleoptera,  mimicking  hymenoptera,  267 
mimicked  by  orthoptera,  268 
offensiveness  of,  244 
as  models  for  mimicry,  265,  266,  268 
Colour,  among  animals,  most  widespread 

use  of,  for  protection,  205 
origin  of,   not  explained   by   variable 

protective  resemblance,  240 
adjustment  of,   is    adaptive,    241  ;    is 
produced  and  maintained  by  natural 
selection,  241 

protection  as  derived  from,  203,  242 
of  surroundings,  exact  reproduction  of 

general,  208 
changes  of,  to  correspond  with  changes 

of  environment,  226 
bright,  association  of  with  distasteful 

qualities,  246 

Colouring,  external,  adaptation  of,  to  con- 
ditions of  life,  204 

Complete  metamorphoses,  examples  of,  2 
Concealment,  of  Sphinx  ligustri,  208 
brilliancy  may  enhance,  206 
manoeuvre  to  effect,  209 
Conspicuous  colour  in  insects,  •  objection 

to,  243 
Conspicuous  and   nauseous  but  non-vital 

parts,  252 

Conspicuously  coloured  insects,  243 
Courtship,  colours  produced  by,  distinction 
between,      and      warning     colours, 
250 

Crematogaster,  nest  of,  151 
Cricket,  field,  home  of,  108 

mole,  home  of,  107 
Crickets,  mimicking  sand-wasps,  267 
mimicking  tiger-beetles,  268 
metamorphoses  of,  3 
Crop,  22,  53 


"Cuckoo  bees "  and  flies,  273 
Currant  galls,  92 
Cutting  ant,  the,  144 


DANAIDTE,  similarity  to  Heliconidae,  252 
as  models  for  mimicry,  254,  258,  260 
Darwin,  on  "walking-stick"  insect,  222 
on  dimorphism,  230 
on  individual  differences,  231 
Dead  Sea  fruits,  94 
Death's  Head  Moth  as  a  thief,  36 
Deep  burrowers  among  British  wild  bees, 

161 
Defences,  insect,  or  protection  as  derived 

from  colour,  203,  242 
need  of,  by  insects,  203 
variety  of  means  of,  243 
usually  attended  by  warning  colours, 

248 

Defensive  appliances,  combination  of,  ex- 
planation of,  272 

Deterioration  of  organs,  law  of,  when  non- 
employed,  62 
Diet,    changes  of,    at    different   stages   of 

life,  46 
of  lepidoptera,  when  young,  46  ;  when 

mature,  46 
of  hymenoptera,  when  young,  47,  85  ; 

when  mature,  47,  85 
Digestion  of  food  in  stomach,  22 
Digestive  system,  of  larvae,  21 

in  perfect  insects,  21,  22 
Dimorphic  pupae,  certain,  non-susceptible, 

237 

Dimorphism,  228 
its  value,  229 
meaning  obscure,  229,  231 
in  lepidopterous  larvae,  228,  229 
in  perfect  insects,  229,  230 
in  spiders,  229 

action  of  natural  selection  in,  230,  231 
Diptera  mimicking  hymenoptera,  266 

aggressive  mimicry  of,  272 
Distasteful     qualities,      not      necessarily 
associated  with  warning  colours,  248 
association  of  bright  colour  with,  246 
Distinction   between  warning  colours  and 

those  produced  by  courtship,  250 
Drone  fly,  mimicry  of,  267 
Dytiscus,  breathing  apparatus  of,  28 

E 

EAR-WIGS,  metamorphoses  of,  3 
Eggs,  forms  of,  4 

footstalks,  4 

colours,  4 

ornamental  patterns,  4 

outer  coat,  4 

modes  of   deposition,    and    localities 
where  placed,  4 

requirements  for  development,  4 

endurance  of  cold,  5 

of  insects  attacked  by  parasitic  hymen- 
optera, 40 

U    2 


INDEX 


Elephant  Hawk  Moth,  mimicry  of  larva, 

270 
Elizabeth  Peckham,  on  mimicry  of  ants  by 

spiders,  269 

Embryo,  growth  of,  within  egg,  5 
Emission  of  offensive  fluids  by  gregarious 

sawflies,  244 
Epiphytal  orchids,  1 50 
Eristalis,  mimicry  of,  267 
Erycinida:  mimicking  Heliconidac,  259 
Eumenidae,  homes  of,  87 
Euploeas  as  models  for  mimicry,  260 
Exact  reproduction  of  general  colours  of 

surroundings,  208 
byCicindela,  208 
by  weevils,  209 
Excrement    of   birds,     imitation    of,     by 

caterpillars,  215 
by  mantises,  226 
by  moths,  218 
by  spiders,  226 

Exotic  species  of  Megachile,  84 
Explanation,   an,   of  sexual  difference  of 

form  and  colour,  263 
of  metamorphoses,  30 

External  colouring,  adaptation  of,  to  con- 
ditions of  life,  204 

External   structures    implicated   in   meta- 
morphoses, 15 


FALSE  LEGS,  structure  of,  16 
Feeding,  capacity  of  insects  for,  6 

insects'  time  of.  58 
Female  butterflies,  more  frequently  mimetic 

than  males,  261 
Field  cricket,  home,  108 
Fleshy  projections  on  larvae,  use  of,  212.  214 
Flies,  the  prey  of  ant-like  spiders,  273 

coarctate  state  of,  10 
Florida  harvester,  57,  135,  140 
Food,  chief  sources  of,  34 

from  manufactured  objects,  36 

insects'  means  of  procuring,  65 
Forbes,  Mr.,  on  resemblance  of  a  spider  to 

excreta  of  birds,  226 
Foresight  of  ants,  remarkable  instance  of, 

Formation  of  homes,  a  remarkable  phase 

of  habits  of  insects,  71 
Formica  ntfcscens,  50 

fuliginosa,  146 

athiopS)  147 

sanguinea,  50 

ftava,  147 

fusca,  architecture  of,  131  ;  mode  of 
heightening  habitation,  132  ;  Huber 
on,  132  ;  muscular  power  of,  132  ; 
preference  for  southern  aspect,  133 

cunicularia,   131 

brunnea,  nest  of,  128 

elata,  151 

bisj>inosa,  153 

Forms  of  animal  life,  more  advanced,  pro- 
duced by  Old  World  than  New,  164 


Fossorial  hymenoptera,  85 
strange  food  of  young,  85 
Odynerus,  homes  of,  86 
sand-wasps,  87 

Frequency  of  moults  of  larva,  7 
Freshly-formed  pupa?,  description  of,  9 


GAD  FLIES,  parasitism  of,  37 
Galleridae,  caterpillars  of,  42 
Gall  flies,  or  Cynipidae,  their  habits,  90 
Gall  makers  other  than  Cynipidae,  95 
Galls,  89,  91 

oak  especially  subject  to,  89,  91 

cherry,  91 

spangle,  92 

currant,  92 

Robin  Redbreast's  pincushion,  92 

of  commerce,  93 

Dead  Sea  fruits,  94 

oak  apples,  91 

Garden  Whites,  see  Pieridae 
Geometrae,    larvae    of,    special    protective 

resemblance  of,  210 
Goat  moth  caterpillar,  increase  of,  7 

a  burrower  into  wood,  97 
Gosse,  Mr.,  on  trapdoor  spiders,  112 
Grasshopper,  crop  in,  22 

mimicry  of,  268 

metamorphoses  of,  3 
Great    development    of   thorax,    when   it 

occurs,  1 8 
Gregarious   habit  of  caterpillars,    itself  a 

"warning,"  248 
Gregarious  sawflies,  emission  of  offensive 

fluids,  244 
Guardians  of  plants,  ants  as,  149 


H 


HABITATIONS,  of  solitary  larvae,  95 
simplest  form  of,  95 
of  solitary  insects  for  young,  73,  89 
of  solitary  architects  for  own  use,  72, 

95»  Jo? 

Hairs,  irritating,  of  caterpillars,  245 
Halictus,  homes  of,  74 
Harmony  of  colouring  between  insects  and 

tints  of  nature,  commonness  of,  206 
Harvesting  ants,  in  East,  55  ;    record  in 

Mishna  of,  55 

of  Europe,  55,  145;  nests  of,  145;  domes 
wanting  in  nests,  145  ;  prevention  of 
germination  of  seeds  by,  56 
in  America,  56,  135  ;  disks  of,  56,  135, 

140  ;  harvest  fields  of,  56,  137 
Head   of  insects,    made   up  of  segments, 

number  of,  19 
appendages  of,  19 
Heliconidae,  similarity  to  Danaidae,  good 

results,  252 

as  models  for  mimicry,  255,  258 
Heliconoid  Danaidte,  252 


INDEX 


293 


Hemiptera  mimicking  hymenoptera,  268 

Hepialidae.  caterpillars  of,  96 

Hermit  homes,  71 

Heteromorpha,  the  series  so-called,  3 

Hive  bee,  73,  156,  162,  164,  267 

Homes,  hermit,  71 

necessary  to  insects,  71 
of  spiders,  English,  109,  115 
social,  118 

Homomorpha,  the  series  so-called,  3 
Honey  ant,  51,  53,  144 
the  rotunds,  51 
analogy  between  economy  of  and  that 

of  bee  in  storage  of  food,  51 
Dr.  McCook  on,  53 
Sir  John  Lubbock  on,  53 
nests  of,  144 
habits  of,  52,  144 
Honey  bees  in  East,  162 
Honey  wasps,  198,  200 
St.  Hilaire  on,  199 

Hornet's  nest,  compared  with  wasp's,  178 
favourite  spots  for,  178 
frequent  absence  of  envelope,  178 
entrances  to  envelope,  use,  179 
sometimes  great  size  of,  180 
materials  for  manufacture  of  envelope, 

1 80 

Reaumur  on,  179 

Hornet  Clear-wing,  mimicry  of,  265 
House-builder  moth,  103 
Huber,  on  ash-coloured  ant,  132 

on  F.  brnnnea,  129 
Humble  bees,  state  of,  at  first  emergence 

from  cells,  13 
in  North  America,  163 
as  models  for  mimicry,  265,  273 
Hydrocampidae,  larvae  of,  107 
Hymenoptera,  fossorial,  85 

mimicked  by  lepidoptera,  263 
mimicked  by  diptera,  266,  272 
mimicked  by  coleoptera,  267 
mimicked  by  orthpptera,  267 
mimicked  by  hemiptera,  268 
dimorphism  among  females,  229,  231 
as  models  for  mimicry,  265,  266,  267 

268,  272,  273 

sting  of,  a  means  of  defence,  246 
warning  colours  of,  247 
offensiveness  of,  244 
Hyinenopus  bicornis,  223 


Ic ARIAS,  description  of  nests,  183 

problems  of  economy  of  societies  of, 

184 

Imago  state,  assumption  of,  12 
Imitation  of  surroundings,   manoeuvre  to 

effect,  209 

Incomplete  metamorphoses,  examples  of,  3 
I  ncrease  of  larva,  reasons  for,  7 
Individual  differences,  Darwin  on,  231 
Insect  architecture,  diversity  of  method, 

118 


Insect  architecture,  its  beauty,  118 
size  as  coanpared  with  makers,  118 
propriety  of  use  of  word,  119 

Insect    parasites     upon     insects,    mighty 
business  of,  40 

Insects,  means  of  procuring  food,  65 
which  mimic  vertebrates,  270,  271 

Instruments  of  nutrition  of  insects,  58 
for  biting,  59 
for  sucking,  59 
reduction  to  one  design,  59 

Internal   organs,   modification  of,    during 
metamorphoses,  21 

Intimate  connection  of  ants,  with  cocci,  45, 

.I5° 
with  beetles,  45 


KALLIMA,  protective  resemblance  of,  215 


LADY-BIRDS,  as  models  for  mimicry,  268 

eject  disagreeable  fluids,  245 
Lamia  ainputator,  larvae  of,  99 
Larva,  produced  alive,  3 

meaning  of  term,  5 

English  terms  for,  5 

change  to  pupa,  8 

stage,  especially  liable  to  parasites, 
reason  of,  40 

cold,  damp,  effects  on,  8 
Larva  of  Puss  Moth,  mimicry  of,  271 

elaborate  means  of  defence  of,  272 
Larva  of  Tabby,  its  partiality  for  grease, 
41 

adaptation  of  structures  for  mode  life, 

41 
evolved  from  ancestors  living  different 

lives,  41 

Larvae,  solitary  habitations  of,  95 
Larvae     of    Coleoptera,     burrowers     into 

wood,  98 
Scarabaeidoe,  98 
Scolytiis  destructor,  98 
Calandra,  99 
Titan-its  gigantens,  99 
Lamia  amputator,  99 
Larvae  of  flies,  destitute  of  legs,  16 
Larvae  of  Geometrae  as  instances  of  special 

protective  resemblance,  210 
Larvae,  leaf-mining,  102 
Larvse    of  Lepidoptera,    burrowers     into 

wood,  95 

of  Sesia  apiformis,  95 
Hepialidae,  96 
Goat  moth  caterpillar,  97 
Larval  life,  length  of,  8 
Leaf-butterflies,  215  _  _ 
Leaf-cutting  propensities  of  ant,  Sauba,  134 
Leaf-cutting  bees,  82 

Megachile,  curious  homes  for  young, 
82 ;  account  of  genus,  82  ;  method 
of  obtaining  building  material,  83 


294 


INDEX 


Leaf-cutting  bees — 

M.  centuncularis  82 

the  upholsterer,  84 

exotic  species,  84 
Leaf-insects,  221 
Leaf-rolling  caterpillars,  101,  102 
Leaf-sewing  caterpillars,  102 
Lecheguana,  199 
Legs,  larva?  of  flies  destitute  of,  16 

difference  between  true  and  false,  17 
Length,  of  larval  life,  8 

of  life  of  insects,  14 
Lepidoptera,  mimicry  in,  254,  258 

protective  resemblance    to   bark    and 
lichen,  213,  214,  218 

offensiveness  of,  244,  245 

protective  pupal  covering  of,  10 

high  adaptation  to  floral  diet.  62 

mimicking  hymenoptera,  265 
Lepidopterous  eggs  attacked  by  parasites, 

40 

Leptalis,  mimicry  in,  259 
Life  history  of  insects,  character  of,  2 

story  of,  5 

often  an  ephemeral  span,  14 
Linnaeus,  on  adoption  of  term  larva,  5 
Locomotion,  acquisition  of  power  of,  at  end 

of  pupal  period,  12 
Locusts,  voyages  of,  29 

metamorphoses  of,  3 

mimicking  a  tiger-beetle,  268 
Lubbock,    Sir    John,    on    ants    as  cattle 
breeders,  44 

on  honey  ant  of  Australia,  53 
Lycosa.  piratica,  117 
Lycosides,  113 

M 

MANNER  of  adjustment  of  pupal  colour, 

discarded  theory,  233 
Manoeuvre,  to  effect  imitation  of  surround- 

_  ings,  209 

Mantidse,  aggressive  resemblances  in,  223, 
226 

aggressive  mimicry  of,  272 
Mantis,  resembling  white  ants,  272 
Mantises,  resemblance  to  flowers,  223 

to  excreta  of  birds,  226 
Mason  ants,  51,  119,  128 

nest  of  F.  brunnea,  129 

building  material,  129 

Huber  on,  129, 130 

moisture  necessary  to,  130 

work  after  dusk  and  during  rain,  131 

of  New  World,  51,  56,  135 
Mason  bees,  social,  164 
Mason  bees,  solitary,  79 

Osmia  and  Chalicodoma,  architecture 
of,  79 

C.  muraria,  building  operations,  79 

occupation  of  old  nests,  81 
May-fly,  pseudo-imago  state  of,  13 
McCook,  Dr.,  on  honey  ant,  53 

on  Occident  ant  of  American  plains, 
M3 


Megachile,  82 

Meldola,  on  photographic  sensitiveness  of 

chrysalides,  233 

Prof.,  on  the  larva  of  S.  ligustri,  227 

Prof. ,  explanation  of  general  similarity 

in  groups  of  unpalatable  butterflies, 

25i 

on   aggressive     mimicry    of    ant-like 

spiders,  273 

Meliponafasciculata,  164 
Mehponae,  domestication  of,  166 

supposed    presence  of  several    fertile 

females  in  colonies,  164 
homes  of,  compared  with  hive,  164 
restricted  to  New  World,  166 
Metamorphic  stages,  considered  in  detail,  3 

changes,  apparent  suddenness  of,  31 
Metamorphoses  of  insects,  i 

study  of  structures  implicated  in,  15 
explanation  of,  30 
old  ideas  of,  14 
modern  theory,  14 
is  a  progressive  development,  15 
Mimetic  analogies  among  beetles,  265 
Mimicry,   a    phase  of  protective    resem- 
blance, 258 
natural  selection  concerned   alike   in 

both  phenomena,  258 
the  term,  257 

true,  confined  to  tropics,  cause  of,  274 
frequency  and  perfection  of,  in  insects, 

some  reasons  of,  274 
as  distinct  from  all  warning  appear- 
ances, 256 

two  supposed  explanations  of,  263 
is  produced  by  natural  selection,  258, 
262  ;  conclusive  argument  in  favour 
of  theory,  262 
Bates,  Mr.,  on,  254 

Mimicry  of  ants  by  spiders,  269,  272,  273 
Mimicry  of  butterflies,  American,  255,  258 
Asiatic,  260 
African,  260 

Mimicry  of  coleoptera  by  orthoptera,  268 
Mining  bees,  74 
Andrenidse,  74 
Halictus,  74 

Mishna,  record  of  ants  in,  55 
Modification    of    internal  organs  during 

metamorphoses,  21 
Mole  cricket,  home  of,  107 
Moths,  British  and  European,  special  pro- 
tection of,  218 
Moults  of  larvae,  6 
frequency  of,  7 

Moults  of  lining  of  internal  organs,  6 
Mouth  organs,  as  appendages  of  head,  19 
Miiller,  Fritz,  explanation  of  resemblance 

of  unpalatable  butterflies,  251 
upon  a  S.  American  Swallow-tail,  237 
Mushroom  growers,  saiiba  ants  as,  135 
Muslin  moth,  probable  mimicry  of,  260 
Mygalida?,  tunnels  of,  109 
Myrapctra  scutellaris,  196 

tuberculated  covers  of  nest,  197 

nest,  formed  of  dung  of  Capincha,  197 


INDEX 


295 


Myrctpetrct  scutellaris — 

longitudinal  section  through  nest,  198 

as  a  honey  gatherer,  198 
Myrmecophilous,  or  ants'-nest  beetles,  45 
Myrmica  Kirbii,  151 


NATURAL   SELECTION,   theory  of,  solves 
principle  of  adaptive  colouring,  205 

part  played  by,  in  association  of  bright 
colour  with  distasteful  qualities,  247 

and  mimicry,  258,  262 
Nectar  of  flowers,  specially  attractive  to 

insects,  36,  62,  63 
Nectarinia,  admired  globular  nests  of,  200 

where  found,  200 

construction  of  nest,  200 

their  flight  of  stairs,  201 

method  of  enlargement  of  nest,  202 

enormous  cell-capacity  of  nest,  202 
Need  of  insects  of  means  of  defence,  203 
Nervous  system,  in  insects,  23 

design  of,  constant,  23 

in  vermiform  larvae,  23 

modification  of,  for  perfect  insects,  24 
Nests,  wasps',  principles  of  enlargement, 

i7S 
Newport,  on  chitine,  20 

on  moulting  of  skin,  20 
Nurses,    need    of,    by    young     of    social 

hymenoptera,  47 
Nursing  bees,  48 
Nutrition,  instruments  of,  58 
Nymph,  term  for  pupa  stage,  10 


OAK  especially  liable  to  galls,  89,  91 
Oak-apples,  91 

Occident   ant   of  American  plains,  where 
found,  140 

architecture,  140 

"clearing,"  reason  for,  140 

path-ways  absent,  why,  141 

roofing  of  mound,  entrances,  142 

interior  of  nest,  143 

habits    different    from    Agriculturist, 
140,  141,  142,  143 

Dr.  McCook  on,  143 
Odynerus,  86,  267 
lEcophylla  sinaragdina,  152 
Old   world,  has  produced  more  advanced 
forms  of  animal  life  than  New,  164 

Meliponae,  absence  of,  in,  166 
Orchids,  epiphytal,  150 
Orthoptera,  offensiveness  of,  244 

mimicking  coleoptera,  268 

protective  resemblance  in,  219 

mimicking  hymenoptera,  267 

metamorphoses  of,  3 
O.smia,  homes  in  shrubs,  81 

contrivances    in     snail-shells,     under 
stones,  8 1 


PAPILIOS,  mimicry  in  African,  260 
mimicry  in  South  American,  259 
mimicry  in  Asiatic,  260 
as  objects  of  mimicry,  260 
Parasites,  37 

insect  pests,  and  vegetables,  balance 

of  life  between,  41 
a  protection  to  pur  crops,  40 
upon  insects,  mighty  business  of,  40 
adult  insects  subject  to,  40 
Parasitic  bees,  49,  273 
Parasitic  hymenoptera,  38,  49,  273 
habits  of,  38  ;  unvarying,  39 
condition  of  insects  attacked  by,  38 
their  power  to  detect  victim  concealed 

from  sight,  39 
their   power    to   gauge    appetites    of 

young,  39 

eggs  of  insects  attacked  by,  40 
Parasol  ant,  134 

Patterns,  similarity  of,  for  warning,  250 
Peckham,  Elizabeth,  on  mimicry  of  ants 

by  spiders,  269 
Pelopaeus,  88 
Pensile  nests,  of  Crematogaster,  151 

of    Formica    elata,    and    Myrmica 

Kirbii,  151 

vlCEcophylla  smaragdina,  152 
Period  of  quiescence,  the  death-like,  n,  33 
Photographic  sensitiveness  of  chrysalides, 

Meldola  on,  233 
Phytophagous  insects,  how  kept  in  check, 

40 
Pieridae,  mimicking  Heliconidae,  259 

females  more    beautiful    than    males, 

262 

Polistes,  description  of,  180 
system  of  nidification,  180 
shape  of  nest,  variable,  181 
nest   protected   by    varnish,   position 

&c.,  1 80,  181 
problems  of  economy  of  societies  of, 

183,  184 

Polistes  aterrima,  182 
Polybia,  nests  of,  193 

P.  palmar urn^  and  seifiela,  193 

P.  liliacea,  195 

P.  rejecta,  196 

principle  of  enlargement  of  nests,  194, 

.J96. 

direction  of  cells,  196 
communication  in  nests,  196 
Possibility  of  enlargement   in   all   honey- 
feeding  ants,  54 

Poulton,  Mr.,  experiments  on  variable 
protective  resemblance,  233  ;  deter- 
mination of  period  of  susceptibility, 
234  ;  of  organ  or  part  susceptible, 

235 
on   insects  which   mimic  vertebrates 

271 

Power  of  locomotion,  acquisition  of,  at 
end  of  pupal  period,  12 


296 


INDEX 


Predaceous    insects    that    resemble   their 

prey,  272,  273 

or  a  form  to  which  their  prey  is  in- 
different, 273 
Privet   Hawk   Moth,  brilliant  colour  of, 

enhances  concealment,  208 
change  of  colour  of  larva,  227 
Problems    of  economy    of    societies,    of 

Polishes,  183,  184 
of  Icarias,  184 

Proboscis  of  butterflies,  how  formed,  60,  62 
appendages  of,  63 
use  of,  62,  63 
position  in  rest,  63 
various  lengths,  64 
ascent  of  fluid  in,  64 
Protection  of  insects  by  means  other  than 

protective  colouring,  243 
by  nauseous  properties,  244 
by  irritating  hairs,  and  spines,  245,  246 
by  the  sting,  246 
hardness  of  substance,  &c.,  246 
Protective  mimicry,  254 
in  lepidoptera,  254,  258 
by  female  butterflies  only,  261  ;  inter- 
pretation    of    phenomenon    affords 
confirmation  of  theory  that  mimicry 
is  produced    by  natural    selection, 
262 

in  British  lepidoptera,  260 
Protective  pupal  covering  of  Lepidoptera, 

10 
Protective  resemblance,  204 

herein  find   explanation    of  first  and 
most  widespread  use  of  colour  among 
animals,  205 
in  butterflies  and  moths,  209,  215,  218, 

.   2I9L 

in  orthoptera,  219 

in  beetles,  bugs,  spiders,  208,  209,  222 

specialised  forms  of,  210 

distinguished  from  protective  mimicry, 

252,  256,  258 

Providence  of  European  ants,  55,  57,  146 
Pseudo-imago,  13 

Psithyrus,  aggressive  mimicry  of,  273 
Psychidae,  building  performances  of,  103 
Pupa,  state  of,  various  terms  for,  10 

meaning  of  term,  10 

nature  of  condition   in   insects    with 
complete  metamorphoses,  n,  33 

length    of    period,    n  ;    determining 
causes,  12 

indications  of  approaching  change,  12 

change  to  imago,  13 
Pupae,  freshly-formed,  description  of,  9 

shelters  for,  8 

butterflies,  preparation  for  change  to,  9 
Puss  Moth,  mimicry  of  larva,  271 

elaborate  means  of  defence  of  larva, 
272 


QUIESCENCE,  of  the  death-like  period  of, 
",  33 


RAFT  spider,  u6 

Reaumur,  experiments  of,    regarding   de- 
velopment of  chrysalis,    12 

on  hornet,  179 

on  Chartergus  chartarius  188 
Regionsof  body  of  insects,  how  formed,  15 
Remarkable  instance  of  foresight  of  ants, 

Resemblance,    between    warning   colours 
and  patterns,  determining  causes  of 
repetition,  249,  250 
of  spiders  to  ants,  explanation  of,  270, 

272,  273 
of  mantis  to  white  ants,  explanation, 

272 
Respiration,    increase   of,    at    change    to 

imago,  12 

of  insects  in  water,  27,  28 
Respiratory  system  in  insects,  26 
Restriction,  of  larger  herbivorous  animals 

to  certain  parts  of  plants,  35 
of  one  species  of  insect  to  one  species 
of  tree  for  resemblance  sake,   209  ; 
usefulness  of,  209 
usual,  of  insects  to  vegetable  or  animal 

diet,  45  ;  exceptions,  45 
Retarded  birth  of  insects,  3 
Robin-Redbreast's  pincushion,  92 


SALIVARY  GLANDS,  23 

in  lepidopterous  larvae,  19,  23 
Sand-wasps,  87 

as  models  for  mimicry,  267 
Saiiba  ant,  133 

nests  where  found,  133 

domes,  133 

underground       earth-works,        extra- 
ordinary dimensions  of,  133 

Mr.  Bates  on,  134 

chambers,  entrances,  latter  generally 
closed,  134 

leaf-cutting  propensities,  134 

as  mushroom  growers,  135 
Saus-ure,  on  entrances  to  nest  hornet,  179 
Sawflies,  defensive  fluid  of  larvae,  244 

as  objects  of  mimicry,  267 
Scarabaeidae  beetles,  larvae  of,  98 
Scolytiis  destructor,  larvae,  98 
Segments,  body  of  insects  formed  of,  15 

of  thorax,  how  recognised,  17 
Scsia  apiformis,  caterpillars  of,  95 
Sesiidse,  mimicry  of,  265 
Sexton  or  burying  beetles,  37 
Sexual  difference   of  form  and  colour,  an 

explanation  of,  263 

Sexual  colours,  made  use  of  for  warning, 
251  ;  their  similarity,  251 

their  transition  to  warning  colours,  251 

and      warning     colours,      difference 
between,  250 


INDEX 


297 


Shelters  for  pupae,  8 
Silk  of  lepidopterous  larva,  19 
Similarity  between  unpalatable  forms,  their 
possession  of  element  of  mimicry,  252 
Size,  of    inssct-architecture   as  compared 

with  makers,  118 

of  tracheae  of  larvae  of  bee  family,  27 
Skin  of  insects,  18.  20 
Snakes  as  models  for  mimicry,  270 
Social,    wasps    and    bees,    feeding    their 

young,  48,  49 
homes,  118,  154 
caterpillars,  societies  of,   119 
Solitary,  homes,  various  kinds  of,  73 
bees,  73 
architects,  homes  of,  for  own  use,  95, 

107  ;  for  young,  72 
Spangle  galls,  92 

Specialised     forms    of  protective    resem- 
blance, 210 

Sphecia  apiformis,  mimicry  of,  265 
Sphingidae  as  honey-gatherers,  64 
Sphinx  ligustri,  increasa  of,  7 

brilliant  colour  of,  enhances  conceal- 
ment, 208 

change  of  colour  of  larva,  227 
Prof.  Meldola  on,  227 
Sphinx  moths,  length  of  pupal   period  of, 

ii 
Spiders,  resembling  ants,  explanation  of, 

270,  272,  273 

ordinary  tube-constructing,  109 
homes  of,  English,  109,  115 
protective  resemblance  of,  222 
resemblance  to  flowers,  224 
resemblance  to  excreta  of  birds,  226  ; 

explained  by  natural  selection,  226 
mimicking  ants,  269,  272,  273 
Spilosoma  menthastri,  probably  a  model 

for  mimicry,  260 
Spinneret,  the,  19 
Spiracles,  26 

position  and  design  of,  27 

of  abdomen  and  of  thorax  compared, 

27 

St.  Hilaire,  on  honey  wasps,  199 
Standing  army  of  bull's  horn,  149 
Stick  caterpillars,   special  protective    re- 
semblance of,  2 10 

Stingless  bees  of  South  America,  163,  166 
Meliponae,  163,  166 
supposed   presence    of  several   fertile 

females  in  colonies,  164,  166 
homes  of,  compared  with  hive,  16}. 
M.  fasciculata^   164 ;  appoints  senti- 
nels to  guard  the  gates,  165 
Trigona,  nests  of,  166 
Stomach,  the,  21,  22 

digestion  of  food  in,  22 
Story  of  life-history  of  insects,  5 
Strange  food  of  young  of  fossorial  hyinen- 

pptera,  85 

Strepsiptera,  parasites  on  bees,  37 
Structure  of  a  wing,   18 
Study  of  structures  implicated  in  metamor- 
phoses, 15 


Synageles  picata,  mimicry  of,  269 
Syneiitosyna  formica,  mimicry  of,  269 


TABBY,  larva  of,  41 
Tatuz  jnorio,  and  nest,  192 
Thorax,  development  of,  17 

appendages  of,  16,  18 

segments  of,  how  recognised,  17 

great  development  of,  when  it  occurs, 

18 

Thrips,  metamorphoses  of,  3 
Tiger  beetle,  a,  an  object  of  mimicry,  268 
Tiger  beetles,  habits  of  larvae,  100 

colour  of,   an  exact  reproduction  of 

colours  of  surroundings,  208 
Tinea  tapetzella,  tube  of,  103 
Tineina  and  Tortricina,  caterpillars  of,  101 
Titanus  giganteiis,  larvae  of,  99 
Tracheae,  and  spiracles,  function  of,  26 

formation  of,  26,  27 

development  into  vesicles,  28  ;  use  of, 
28 

of  larvae  of  bee  family,  size  of,  27 
Tracheal  vessels  of  humble  bee,  29 
Trap-door  spiders,  no 

typical  nest,  no 

barricading  door,  112 

of  southern  Europe,  113 

multiplication  of  precautionary   mea- 
sures, 113 

Mr.  Gosse  on,  112 
Treat,     Mrs.,    on     a     dome-constructing 

spider,  114 

Tree  wasps,  British,  175 
Trichoptera,  homes  of  larvae,  105 
Trigona,    exists   both   in   Old    and    New 
Worlds,  163,  166 

honey  of,  166 

nests  of,   1 66 

True  legs  of  insects,  their  nature,  develop- 
ment, 16,  17 

Tube  of  Tinea  tapetzella,  103 
Turret  spiders,  113 
Two  classes  of  legs,  number  of,  16 


U 


UNDERSIDES  of  wings  of  butterflies,  sober 

tints  of,  209 

imitative  tints  of,  209,  215,  216,  253 
concealment  afforded  effective,  210,  216 
Unpleasant   qualities  possessed  by  cater- 
pillars, 244,  245,  246 
Upholsterer,  the,  bee,  84 


VAKIABLE  protective  resemblance,  231 

history  of  discovery  of,    in   pupse    of 

butterflies,  232 
in  caterpillars,  Mr.  Poulton  on,  239 


INDEX 


Variable  protective  resemblance — 

in  cocoons,  240 

probable  in  certain  perfect  insects,  240 

no  explanation  of  the  origin  of  colour, 

240 
Vegetable  food,  choice  of,  almost  limitless 

for  insects,  34 
Vegetation  that  is  poisonous  or  distasteful 

to  higher  animals,  35 

Vertebrates,  insects  which  mimic,  270,  271 
Vespa.    britannica,    beautiful     globe-like 

dwelling  of,  175 

Vespa  orientalis,  an  object  of  mimicry,  266 
Vespa  vulgaris,  particulars  of  home,  168 

formation  of  home,  and  of  society,  169 

dissolution  of  company,  173 

pendent  nests  of,  175 

as  object  of  mimicry,  272 
Vespidae,  167 

beauty  and  delicacy  of  architecture, 
167 

building  material,  168 

disposition  of  combs,  168 
Vine,  caterpillars  destructive  to,  101 
Volucella,  aggressive  mimicry  of,  272 
Voyages  of  locusts,  29 

W 

"  WALKING  LEAF  "  insect,  221 
"Walking  stick"  insects,  221,  222 
Wallace,  on  Kalliina  paralekta,  215,  217 
on  a  "walking  stick"  insect,  221 
on  dimorphism,  230 
on  protective  mimicry  in    British   le- 

pidoptera,  260 
on    liability   of   female  butterflies   to 

assume  protection  of  mimicry,  262 
Warning,  sexual  colours  made  use  of  for, 

25i 

Warning,  a,  bright  colour  as,  247 
Warning  colours,  and  those  produced  by 

courtship,  distinction  between,  250 
defences  usually  attended  by,  249 
and  patterns,  resemblance  between,  249 
in  caterpillars,  244,  245 
Wasp,  defensive  bright  colours  of,  247 
Wasps,  as  objects  of  mimicry,  265,  266,  267, 

272 

British  tree,  175 
as  honey  gatherers,  198,  200 
Wasps'  nest,  enlargement  of,  175 

papery  envelope  of,   its    fabrication  ; 
imbrication  of  sheets,  176,  177 


Wasps'  nests,  without  cover,  180,  183 

with  cover,  but  not  distinct,  184 
Water-spiders,  115 

Wax,  caterpillars  with  a  liking  for,  42 
Weevils,  subject  to  parasites,  40 

colour  of,  exactly  reproduces  colour  of 

surroundings,  209 

White  ants  as  objects  of  mimicry,  272 
White  Ermine  Moth,  probable  object  of 

mimicry,  260 

Wild  bees,  British.  74,  79,  82,  154 
Wings,    condition    of,   at    assumption  of 

imago  state,   13 
of  butterflies,  meaning  of  dull  colours 

of  undersides  of,  209,  210 
attachment  of,  17 
structure  of,  18 

association  of,   with   function  of   re- 
spiration, 1 8 
broad  expanse  of,  of  showy  butterflies, 

one  explanation  of,  253 
Wood  carved  by  F.  fuliginosa  becomes 

black,  147 

Wood  ant,  home,  120 
various  names  of,  120 
external  conformation  of  home,  120 
internal  plan  of  dome,  and  dwelling 

underground,  120,  122 
doors,  122 
swarming,  and  regulation  of  society, 

123      ' 

care  of  young,  124 
a  solitary  "queen"  as  founder   of  a 

colony,  126 
singularity  of  preference  for  open-air 

life,  127 

precaution  against  attack,  122,  127 
closure  of  apertures  of  dwelling,  127 
in  Scotland,  128 
in  warm  climates,  128 
Wood-carving  ants,  146 
F.  fnliginosa,  146 
F.  aethiops,  habits  of,  147 
F.jffava,  habits  of,  147 


Xylocopa  violacea,  interesting  home  of,  75 


YELLOW  ant,  ingenuity  in  building,  147 


THE    END. 


RICHARD  CLAY  AND  SONS,  LIMITED,  LONDON  AND  BUNGAY. 


MACMILLAN  &  CO/8  PUBLICATIONS, 

BOOKS  BY  SIR  JOHN  LUBBOCK,  M.P.,  F.R.S. 

ON  THE  ORIGIN  AND  METAMOR- 
PHOSES OF  INSECTS.  With  Numerous  Illus- 
trations. Crown  8vo,  3*.  6d.  [Nature  Series. 

ON    BRITISH    WILD    FLOWERS,    con- 

sidered  in  Relation  to  Insects.     With  Numerous  Illus- 
trations.    Crown  8vo,  4*.  6d.  {Nature  Series. 

FLOWERS,    FRUITS,    AND     LEAVES. 

With  Illustrations.     Crown  8vo,  45.  6d. 

[Nature  Series. 

THE  BEAUTIES  OF  NATURE.     Crown 

8vo,    6s.      New  Edition,  without  Illustrations,    Globe 
8vo,  Paper,  is.,  Cloth,  is.  6d. 

THE    PLEASURES   OF    LIFE.     PART  I. 

Globe  8vo.     Popular   Edition,     is.  6d.  ;    sewed,    is. 
Library  Edition.     $s.  6d. 

THE  PLEASURES  OF  LIFE.     PART  II. 

Globe   8vo,    is.  6d. ;    sewed,     is.     Library    Edition. 
3s.  6d. 

THE     PLEASURES      OF    LIFE.     (Two 

Parts  in  one  Vol.)     Globe  8vo,  2s.  6d. 

SCIENTIFIC      LECTURES.       Second 

Edition.     8vo,  8s.  6d. 

ADDRESSES,  POLITICAL  AND  EDU- 
CATIONAL. 8vo,  8s.  6d. 

FIFTY     YEARS    OF    SCIENCE.     Being 

the  Address  delivered  at  York  to  the  British  Associa- 
tion, August,  1 88 1.     Fifth  Edition.     8vo,  2s.  6d. 

MACMILLAN  AND  CO.,  LONDON. 


MACMILLAN  &  GO/8  PUBLICATIONS. 

BOOKS  BY  DR.  A.  R.  WALLACE,  F.R.S. 

THE  MALAY  ARCHIPELAGO:    THE    LAND 

OF  THE  ORANG-UTAN  AND  THE  BIRD  OF  PARADISE. 

A   Narrative  of    Travel.     With   Studies    of     Man  and   Nature. 

By  ALFRED  RUSSEL  WALLACE,  LL.D.,  F.L.S.,  Author 

of  "  Darwinism,"  &c.      With  Maps  and   Illustrations.      Fourth 

Edition.     Extra  crown  8vo,  6s. 

GLASGOW  HERALD.— "There  is  probably  no  more  interesting  book  of 
travel  in  the  language.  .  .  .  For  one-and-twenty  years  it  has  held  its  place  as  a 
monograph  in  a  region  of  the  East  which  is  full  of  fascination,  not  only  for  the 
naturalist  and  ethnographer,  but  for  the  ordinary  reader  of  travels." 

ISLAND  LIFE:  OR,  THE  PHENOMENA  AND 

CAUSES  OF  INSULAR  FAUNAS  AND  FLORAS.  In- 
cluding a  revision  and  attempted  solution  of  the  problem  of 
Geological  Climates.  By  the  same  Author.  With  Illustrations 
and  Maps.  Second  Edition.  Crown  8vo,  6s. 

THE   GEOGRAPHICAL   DISTRIBUTION    OF 

ANIMALS;  with  a  study  of  the  relations  of  living  and  extinct 
faunas  as  elucidating  the  past  changes  of  the  earth's  surface. 
With  Maps  and  Illustrations.  In  two  Vols.  Medium  8vo,  42^. 

NATURAL  SELECTION  AND  TROPICAL 

NATURE :  Essays  on  Descriptive  and  Theoretical  Biology. 
New  Edition  with  corrections  and  additions.  Extra  crown  8vo, 
6s. 

DARWINISM  :  An   Exposition   of   the  Theory  of 

Natural  Selection,  with  some  of  its  Applications.  By  the  same 
Author.  Illustrated.  Extra  crown  8vo,  gs. 

SATURDAY  REVIEW.— "Mr.  Wallace's  volume  may  be  taken  as  a 
faithful  exposition  of  what  Darwin  meant.  It  is  written  with  perfect  clearness, 
with  a  simple  beauty  and  attractiveness  of  style  not  common  to  scientific  works, 
with  a  dignity  and  freedom  from  anything  like  personal  bitterness  worthy  of 
Darwin  himself,  and  with  an  orderliness  and  completeness  that  must  render  miscon- 
ception impossible." 

ATHENMUM.— "Mr.  Wallace  adds  so  much  that  is  new,  and  he  writes  in  so 
charming  and  simple  a  style,  that  his  readers  more  than  he  are  to  be  congratulated 
on  the  latest  service  he  has  rendered  to  the  science  he  has  served  so  well." 

Prof .  Ray  Lankester  in  NATURE. — "No  one  has  so  strong  a  claim  as  Mr. 
Wallace  to  be  heard  as  the  exponent  of  the  theory  of  the  origin  of  species,  of  which 
he  is — with  Darwin — the  joint  author.  .  .  .  The  book  is  one  which  has  interest 
not  only  for  the  general  reader,  to  whom  it  is  primarily  addressed,  but  also  for  the 
more  special  students  of  natural  history.  The  latter  will  find  in  its  pages  an  abund- 
ance of  new  facts  and  arguments  which,  whether  they  prove  convincing  or  not,  are 
of  extreme  value  and  full  of  interest." 

MACMILLAN  AND  CO.,  LONDON. 


MACMILLAN'S  SCIENCE  PRIMERS. 

Polt  8vo.     Cloth.     is.  each. 

Under  the  joint  Editorship  of  Prof.  HUXLEY,  Sir  H.  E.  ROSCOE,  and 
Prof.  BALFOUR  STEWART. 

INTRODUCTORY. 

By  Professor  HUXLEY,   F.R.S. 

ASTRONOMY. 

By  J.  N.  LOCKYER,  F.R.S.     Illustrated.     New  Edition. 

PHYSICS. 

By  BALFOUR   STEWART,    F.R.S.     With  numerous   Illustrations 
and  Questions.     New  Edition. 

CHEMISTRY. 

By  Sir  H.  E.  ROSCOE,  F.R.S.     With  numerous  Illustrations  and 
Questions.     New  Edition. 

GEOLOGY. 

By  Sir  A.   GEIKIE,   F.R.S.     With  numerous  Illustrations.     New 
Edition. 

PHYSICAL  GEOGRAPHY. 

By  Sir   A.    GEIKIE,    F.R.S.     With  numerous   Illustrations  and 
Questions.     New  Edition. 

BOTANY. 

By   Sir    J.    D.     HOOKER,    F.R.S.     New   Edition,    revised   and 
CDrrected. 

PHYSIOLOGY. 

By  MICHAEL  FOSTER,  M.D.,  F.R.S.  With  numerous  Illustrations. 
New  Edition. 

LOGIC. 

By  W.   STANLEY  JEVONS,  F.R.S.     New  Edition. 

POLITICAL  ECONOMY. 
By  W.  STANLEY  JEVONS,  F.R.S. 

Uniform  with  the  Above. 
FIRST  LESSONS  IN  PRACTICAL  BOTANY. 

By  G.  T.  BETTANY,  M.A.,  F.L.S.     Pott  8vo.     is. 

FIRST  PRINCIPLES  OF  AGRICULTURE. 

By  H.  TANNER,  F.C.S.     Pott  8vo.     is. 

MACMILLAN   AND    CO.,    LONDON. 


ELEMENTARY  SCIENCE   CLASS    BOOKS, 

ALGEBRA  FOR  BEGINNERS.     By  H.  S.  HALL 

M.A.,  and  S.  R.  KNIGHT,  B.A.     2s.     WITH  ANSWERS.     2s.  6J. 
MECHANICS  FOR  BEGINNERS.     By  Rev.  J.  B. 

LOCK,  M.  A.     Part  I.  Mechanics  of  Solids.     2s.  6d. 

SCHOOLMASTER, — ''  Bears  the  stamp  of  an  author  who  is  thoroughly  at  home 
in  his  subject.  Careful  arrangement,  logical  explanation,  suitable  illustratiDns  and 
numerous  examples  testify  to  the  value  of  the  book." 

Part  II.  Mechanics  of  Fluids.  [In  preparation. 

ELEMENTARY  LESSONS  IN  HEAT,  LIGHT, 

AND     SOUND.     By    Prof.    D.     E.    JONES,     B.Sc.      2s.    6d. 

Adapted   to    the    Elementary    Stage    of   the    South 
Kensington  Syllabus. 

The  questions  at  the  ends  of  chapters  are  taken  partly  from  the  Ele- 
mentary Papers  of  the  Science  and  Art  Department. 

ELECTRICITY  AND  MAGNETISM  FOR 
BEGINNERS.  Adapted  to  the  Elementary  Stage  of 
the  South  Kensington  Syllabus.  By  Prof.  s.  P. 

THOM  PSON.  [In  preparation. 

INORGANIC  CHEMISTRY  FOR  BEGINNERS. 

By  Sir  HENRY  ROSCOE,  F.R.S.,  assisted  by  JOSEPH  LUNT,  B.Sc. 

2s.  6d.    Adapted  to  the  Elementary  Stage  of  the  South 
Kensington    yllabus. 

ORGANIC  CHEMISTRY  FOR  BEGINNERS. 
By  G.  S.  TURPIN,  M.A.  Adapted  to  the  Elementary 
Stage  of  the  South  Kensington  Syllabus.  {.Ready  shortly. 

PHYSIOGRAPHY    FOR    BEGINNERS.     By    J. 

E.    MARR,    M.A.,    F.R.S.,    and   A.    HARKER,    M.A.,    F.G.S. 

Adapted   to    the    Elementary    Stage    of   the    South 

Kensington  Syllabus.  [Ready  shortly. 

PHYSIOLOGY    FOR    BEGINNERS.     By    Prof. 

MICHAEL  FOSTER  and  Dr.   L.   E.    SHORE.     Adapted  to  the 

Elementary  Stage  of  the  South  Kensington  Syllabus. 

[Ready  shortly. 

MACMILLAN    AND    CO.,    LONDON. 

4 


SOME  VOLUMES  OF   "NATURE"  SERIES. 

Crown  8vo.     Cloth. 

SEEING  AND  THINKING. 

By  Prof.  W.  K.  CLIFFORD,  F.R.S.     Diagrams.     $s.  6J~ 

POPULAR  LECTURES  AND  ADDRESSES. 

By  Lord  KELVIN,  P. R.S.      In  3  vols.      Vol.1.  Constitution  of- 
Matter.     Illustrated.     'Js.  6d.     Vol.  III.   Navigation.     7-r.  6d. 

MODERN  VIEWS  OF  ELECTRICITY. 

By  Prof.  O.  J.  LODGE,  LL.D.     Illustrated.     6s.  6d. 

A  CENTURY  OF  ELECTRICITY. 

By  T.  C.  MENDENHALL.     45-.  6d. 

CHARLES  DARWIN. 

Memorial  Notices  reprinted  from  "Nature."  By  THOMAS  H. 
HUXLEY,  F.R.S.,  G.  J.  ROMANES,  F.R.S.,  Sir  ARCHIBALD 
GEIKIE,  F.R.S.,  and  W.  T.  DYER,  F.R.S.  zs.  6d. 

THE    SCIENTIFIC     EVIDENCES     OF      ORGANIC 
EVOLUTION. 

By  GEORGE  J.  ROMANES,  F.R.S.     zs.  6d. 

ARE  THE    EFFECTS    OF    USE    AND    DISUSE    IN- 
HERITED?     An    Examination    of  the    View  held  by 
Spencer  and  Darwin. 
By  W.  PLATT  BALL.     33.  6d. 

ON  THE  COLOURS  OF  FLOWERS. 

By  GRANT  ALLEN.     Illustrated.     3$.  6d. 

THE  APODID^:  A  MORPHOLOGICAL  STUDY. 
By  HENRY    MEYNERS   BERNARD,    M.A.    Cantab.       With    71 
Illustrations.     7-r.  6d. 

SCOTSMAN. — "A  book  which  zoologists  will  very  greatly  prize. 
The  writer  has  worked  out  the  task  he  set  before  him  with  the  greatest 
care  and  in  the  most  elaborate  manner,  and  has  presented  the  fruits  of 
his  labour  in  a  volume  which  every  lover  of  scientific  investigation  will 
thoroughly  appreciate.  ...  A  valuable  contribution  to  zoological 
investigation." 

THE  RIGHT  HAND :   LEFT-HANDEDNESS. 

By  SirD.  WILSON.     Illustrated.     4*.  6d. 

MACMILLAN  AND  CO.,  LONDON, 


BOOKS  FOR  THE  COUNTRY. 

WHITE'S  NATURAL  HISTORY  AND  ANTIQUITIES 

.OF  SELBORNE,  With  Notes  by  FRANK  BUCKLAND,  and  a 
Chapter  on  Antiquities  by  LORD  SELBORNE.  Illustrated  by  P. 
H.  DELAMOTTE.  Crown  8vo,  6s. 

FORTY    YEARS   IN    A    MOORLAND   PARISH.     By 

Rev.  Canon  ATKINSON,  D.C.L.  With  Maps  and  Illustrations. 
Extra  crown  8vo.  Ss.  6d.  net.  Illustrated  Edition.  125.  net. 

WALKS,  TALKS,  TRAVELS,  AND  EXPLOITS  OF 
TWO  SCHOOLBOYS.  By  the  same  Author.  With  Illustra- 
tions. Crown  8vo.  35.  6J. 

PLAYHOURS  AND  HALF-HOLIDAYS.  By  the  same 
Author.  New  Edition.  Illustrated  by  COLEMAN.  Crown  8vo. 
3^.  6d. 

TALES  OF  THE  BIRDS.  By  W.  WARDE  FOWLER. 
With  Illustrations  by  BRYAN  HOOK.  Second  Edition.  Crown 
8vo.  3.?.  6d. 

A  YEAR  WITH  THE  BIRDS.  By  the  same  Author. 
With  Illustrations  by  BRYAN  HOOK.  Third  Edition,  enlarged. 
Crown  8vo.  33.  6d. 

HANDBOOK  OF  FIELD  AND  GENERAL  ORNITH- 
OLOGY. By  ELLIOTT  COUES,  M.A.,  M.D.,  Ph.D.,  Member  of 
the  National  Academy  of  Sciences,  &c.  Profusely  Illustrated. 
8vo.  ics.  net. 

NATURE. — "We  know  of  no  volume  likely  to  be  more  useful  to 
the  student  who  wishes  to  become  acquainted  with  birds.  .  .  .  No 
other  manual  that  we  are  acquainted  with  exactly  takes '  its  "place  or 
contains  such  a  well  arranged  mass  of  useful  and  generally  correct 
information  on  this  subject." 

THE     STUDENT'S    FLORA     OF      THE     BRITISH 

ISLANDS.       By   Sir  J.    D.    HOOKER,    F.R.S.      Globe    8vo. 
IDS.  6d. 

MADAM  HOW  AND  LADY  WHY;  OR,  FIRST 
LESSONS  -IN  EARTH-LORE  FOR  CHILDREN.  By 
CHARLES  KINGSLEY.  With  numerous  Illustrations.  Crown  8vo. 
35.  6d. 

GLAUCUS;  OR,  THE  WONDERS  OF  THE  SEA- 
SHORE. By  the  Same.  With  Coloured  Illustrations.  Crown 
8vo.  35-.  6d. 

MACMILLAN  AND  CO.,, LONDON. 

6  •  " 


RETURN     BIOLOGY  LIBRARY 

3503  Life  Sciences  Bldg 


642-2531 


LOAN  PERIOD  1 


ALL  BOOKS  MAY  BE  RECALLED  AFTER  7  DAYS 
books  are  subject  to  immediate  recall 


&   DUE  AS  STAMPED  BELOW 


JJBRARY  USE 


AUE  03 


UNIVERSITY  OF  CALIFORNIA,  BERKELEY 
FORM  NO.  DD4  BERKELEY,  CA  94720 

®s 


